A study of job stress, suicidal ideation and suicide attempts in display manufacturing workers: a crosssectional study

Background@#This study aimed to investigate the association between job stress and suicide ideation/attempts among display manufacturing workers. @*Methods@#Data were collected from 836 workers in a display manufacturing company who participated in health screenings from May 22 to June 16, 2017. The data included general characteristics, night work, job tenure, previous physician-diagnosed chronic diseases, suicidal ideation/suicide attempts, and job stress. We investigated suicidal ideation/suicide attempts that covered the past year by using a self-reported questionnaire. Job stress was measured using the 43-item Korean Occupational Stress Scale. Multiple logistic regression analysis was used to investigate the association between job stress and suicidal ideation/ suicide attempts. The mediator effect of depression on suicidal ideation/suicide attempts was tested using a series of logistic regression by applying Baron and Kenny's mediation method. @*Results@#In the model adjusting for variables (e.g., age, body mass index, smoking, alcohol consumption, regular exercise, shift work, job tenure, chronic disease and depression), physical environment (OR: 3.60, 95% CI: 1.08–12.02), lack of reward (OR: 5.31, 95% CI:1.54–18.34), and occupation climate (OR: 7.36, 95% CI: 2.28–23.72) were correlated with suicidal ideation/suicide attempts in women. However, all subscales of job stress were not significantly correlated with suicidal ideation/suicide attempts in men. In mediation analysis, job instability and occupational climate were correlated with suicidal ideation/suicide attempts and were mediated by depression in men workers. @*Conclusions@#In women workers, the experiences of suicidal ideation/suicide attempts were significantly correlated with the physical environment, lack of reward, and occupational climate that were subscales of job stress. In men workers, depression rather than job stress was correlated with experiences of suicidal ideation/suicide attempts.

A study of job stress, suicidal ideation and suicide attempts in display manufacturing workers: a crosssectional study

Background@#This study aimed to investigate the association between job stress and suicide ideation/attempts among display manufacturing workers. @*Methods@#Data were collected from 836 workers in a display manufacturing company who participated in health screenings from May 22 to June 16, 2017. The data included general characteristics, night work, job tenure, previous physician-diagnosed chronic diseases, suicidal ideation/suicide attempts, and job stress. We investigated suicidal ideation/suicide attempts that covered the past year by using a self-reported questionnaire. Job stress was measured using the 43-item Korean Occupational Stress Scale. Multiple logistic regression analysis was used to investigate the association between job stress and suicidal ideation/ suicide attempts. The mediator effect of depression on suicidal ideation/suicide attempts was tested using a series of logistic regression by applying Baron and Kenny's mediation method. @*Results@#In the model adjusting for variables (e.g., age, body mass index, smoking, alcohol consumption, regular exercise, shift work, job tenure, chronic disease and depression), physical environment (OR: 3.60, 95% CI: 1.08–12.02), lack of reward (OR: 5.31, 95% CI:1.54–18.34), and occupation climate (OR: 7.36, 95% CI: 2.28–23.72) were correlated with suicidal ideation/suicide attempts in women. However, all subscales of job stress were not significantly correlated with suicidal ideation/suicide attempts in men. In mediation analysis, job instability and occupational climate were correlated with suicidal ideation/suicide attempts and were mediated by depression in men workers. @*Conclusions@#In women workers, the experiences of suicidal ideation/suicide attempts were significantly correlated with the physical environment, lack of reward, and occupational climate that were subscales of job stress. In men workers, depression rather than job stress was correlated with experiences of suicidal ideation/suicide attempts.

Relationship of spouses' weekly working hours and sleep problems in Korean wage workers: the 5th Korean working conditions survey

Background@#Sleep disorders are common and serious problems for mental health. This study investigated the relationship between spouses' weekly working hours (SWWH) and sleep problems by using the data from the 5th Korean Working Conditions Survey. @*Methods@#Data from 14,921 wage workers were used in the 5th Korean Working Conditions Survey. General and occupational characteristics, sleep problems are included in the questionnaire. Multivariate logistic regression analysis was used after adjustment for general and occupational characteristics to find the relationship between SWWH and sleep problems. @*Results@#Compared to those whose spouses worked less than 40 hours per week, risk of trouble falling asleep, waking up repeatedly while sleeping, and waking up with a feeling of exhaustion and fatigue was significantly higher as SWWH increase among those whose spouses worked 53 or more hours per week (odds ratio [OR]: 1.40, 95% confidence interval [CI]: 1.16–1.70; OR: 1.50, 95% CI: 1.23–1.82; OR: 1.51, 95% CI: 1.24–1.83). @*Conclusions@#SWWH were related to sleep problems among Korean wage workers.

Relationship of spouses' weekly working hours and sleep problems in Korean wage workers: the 5th Korean working conditions survey

Background@#Sleep disorders are common and serious problems for mental health. This study investigated the relationship between spouses' weekly working hours (SWWH) and sleep problems by using the data from the 5th Korean Working Conditions Survey. @*Methods@#Data from 14,921 wage workers were used in the 5th Korean Working Conditions Survey. General and occupational characteristics, sleep problems are included in the questionnaire. Multivariate logistic regression analysis was used after adjustment for general and occupational characteristics to find the relationship between SWWH and sleep problems. @*Results@#Compared to those whose spouses worked less than 40 hours per week, risk of trouble falling asleep, waking up repeatedly while sleeping, and waking up with a feeling of exhaustion and fatigue was significantly higher as SWWH increase among those whose spouses worked 53 or more hours per week (odds ratio [OR]: 1.40, 95% confidence interval [CI]: 1.16–1.70; OR: 1.50, 95% CI: 1.23–1.82; OR: 1.51, 95% CI: 1.24–1.83). @*Conclusions@#SWWH were related to sleep problems among Korean wage workers.

Occupational Noise Exposure and Serum Lipids in Manufacturing Company Workers

OBJECTIVE: The study aimed to examine the relationship between occupational cumulative noise exposure and serum lipids as risk factor of ischemic heart disease. METHODS: Participants (n=1,175) were workers of the steel product manufacturing factory exposed to more than 85 dB(A) of noise. We collected ambient noise and other materials monitoring data in workplace, laboratory test, and structured-questionnaires. Occupational noise exposure was defined as cumulative noise exposure calculated by duration of exposure and level of exposure. Serum lipids were total cholesterol, triglyceride, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and total cholesterol/HDL cholesterol. We examined the relationship between serum lipids and occupational noise exposure. RESULTS: In a noise exposure environment, 657 people (56.8%) worked for more than 10 years. Cumulative noise exposure increased significantly as exposure duration and noise level increased. Cumulative noise exposure were related to total cholesterol (P=0.001), LDL cholesterol (P=0.002), total cholesterol/HDL cholesterol (P=0.005) in correlation analysis. We conducted multiple linear regression analysis using the serum lipids and significant variables including cumulative noise exposure. We identified that total cholesterol was significantly related to cumulative noise exposure (β=0.072). CONCLUSION: We propose occupational cumulative noise exposure may be significantly related to total cholesterol.

The associations between work-related factors and temporomandibular disorders among female full-time employees: findings from the Fourth Korea National Health and Nutrition Examination Survey IV (2007–2009)

BACKGROUND: The aim of this study was to investigate the association between work-related factors and temporomandibular disorders (TMD) among female full-time employees using representative data from a national population-based survey. METHODS: Data from the Fourth Korea National Health and Nutrition Examination Survey IV (2007–2009) were used to analyze 1,612 women. Complex samples logistic regression was applied for adjusting for general characteristics and work-related factors to examine the association between work-related factors and TMD. RESULTS: The prevalence of TMD was 12.8% in this study population. With respect to age, educational status, marital status, problem drinking, exercise, and stress, there were statistically significant differences in the prevalence of TMD. In logistic regression analyses on complex samples, based on 40 h or less per week, odds ratios (ORs) for respondents who worked 40–48 working hours, 49–60 working hours, and more than 60 h were 1.16 (95% confidence interval (CI) 0.69–1.94), 1.41 (95% CI 0.79–2.54), and 2.43 (95% CI 1.29–4.59), after adjusting for general characteristics, working schedule, employment status, and occupation. CONCLUSIONS: This study found that long working hours were significantly associated with TMD in Korean female full-time employees.

Relationship between job stress and functional dyspepsia in display manufacturing sector workers: a cross-sectional study

BACKGROUND: Job stress has been reported as a risk factor of psychological changes, which have been shown to be related to gastrointestinal diseases and symptoms such as functional dyspepsia. However, few studies have assessed the relationship between job stress and functional dyspepsia. Therefore, we investigated the relationship between job stress and functional dyspepsia in South Korea.

The Process of Compensation of Occupational Diseases in Special Populations: Public Officials, Private School Teachers and Staff, Soldiers, Fishing Crews, and Farmers

OBJECTIVE: The purpose of this study was to review the compensation and development direction of occupational accidents including occupational diseases of workers who do not apply industrial accident compensation insurance. METHODS: We reviewed laws and related articles about compensation for occupational accidents of public officials, private school teachers and staff, soldiers, fishermen, and farmers, and compared each system and presented problems and solutions. RESULTS: Public officials, private school teachers and staff, and soldiers were provided compensation for the occupational accidents by the state in the form of pensions. Safety accident insurance for farmers was a form of voluntary subscription, but the individual had to pay the remaining premiums even though there were over half of the national burden. Although there were differences in the degree of professionalism in approval system of occupational accidents in the fields of public officials, private school teachers and staff, and soldiers, there was a deliberative body composed of experts, but fishermen and farmers were in fact considering deliberations on the compensation of insurance companies. Like the industrial accident compensation insurance, the prevention fund was not legally enforced in all fields. CONCLUSION: Processes for compensation for occupational accidents was somewhat similar. However, scientific and rational deliberations were difficult to achieve consistently. There was a lack of systems to prevent disasters and institutionalize rehabilitation for returning to work after a disaster. It is necessary to introduce a consistent system for reasonable compensation, disaster prevention, and return to work according to the risk level of the special population.

Recent Changes to Improve the Process of Compensation of Occupational Diseases in Workers Covered by the Industrial Accident Compensation Insurance Act

OBJECTIVE: We studied recent changes and improvement in compensation for occupational accidents, including the occupational diseases of workers who apply for industrial accident compensation insurance. METHODS: We reviewed the Industrial Accident Compensation Insurance policy, the regulations and case reports of the Korea Worker's Compensation & Welfare Service, research reports, and press articles to confirm the approval process for, recognition criteria of, and recent trends in occupational diseases. RESULTS: The Industrial Accident Compensation Insurance Act applies to workplaces with one or more regular employees. The approval process for occupational diseases is complicated and requires much time and effort. The Korea Workers' Compensation & Welfare Service needs to conduct an investigation of occupational diseases on its own or, if that would be impossible, it should request an epidemiological investigation or consult with an external professional institution. The Committee on Occupational Disease Judgment requires experts from various fields to participate in order to have consistent and objective reviews. Legal adjustments for commuting disasters have been made since 2018. CONCLUSION: The application of the Industrial Accident Compensation Insurance Act should be expanded to protect more workers. We should improve the recognition process of occupational diseases so that it is done simply and quickly, and we should maintain the expertise and objectivity of the Committee on Occupational Disease Judgment.

Night shift work and inflammatory markers in male workers aged 20–39 in a display manufacturing company

BACKGROUND: This study aimed to determine the association between shift work and inflammatory markers, which are independent risk factors of cardiovascular diseases, in male manual workers at a display manufacturing company. METHODS: This study was conducted between June 1 and July 31, 2015 on 244 male manual workers aged 20–39 years old at a display manufacturing company and investigated age, marital status, education level, alcohol consumption habit, smoking habit, regular exercise habit, sleep duration, sleep debt, sleep insufficiency, past medical history, current and past shift work experience, duration of shift work, and weekly work hours through face-to-face interviews using structured questionnaires and performed blood tests. Study participants were divided into daytime, former shift, and current shift workers based on the work schedule. Chi-square tests and one-way analyses of variance were performed to compare inflammatory markers and cardiovascular disease risk factors, and analyses of covariance were conducted after adjusting for variables potentially affecting inflammatory markers. RESULTS: High-sensitivity C-reactive protein (hs-CRP; mean ± standard deviation) levels in daytime, former shift, and current shift workers were 0.65 ± 0.43, 0.75 ± 0.43, and 0.86 ± 0.72 mg/L, respectively (p = 0.029). The leukocyte count (mean ± standard deviation) was 5,556 ± 1,123, 6,210 ± 1,366, and 6,530 ± 1,216 cells/μL, respectively (p < 0.001). Both hs-CRP level and leukocyte count were significantly higher in current shift workers than in daytime workers, and leukocyte count was higher in former shift workers than in daytime workers. After adjusting for variables potentially affecting inflammatory markers, hs-CRP levels (adjusted mean ± standard deviation) in daytime and current shift workers were 0.59 ± 0.06 and 0.92 ± 0.07 mg/L, respectively (p = 0.002). The leukocyte count (adjusted mean ± standard deviation) was 5,557 ± 124 and 6,498 ± 144 cells/μL, respectively (p < 0.001). CONCLUSIONS: A significant association between shift work and increases in inflammatory markers was confirmed. Because chronic low-grade inflammation plays an important role in the development of cardiovascular diseases, regular follow-up of inflammatory markers as a marker of cardiovascular diseases in shift workers may serve as an early indicator in predicting the effects of shift work on health.

Employment and occupation effects on late-life depressive symptoms among older Koreans: a cross-sectional population survey

BACKGROUND: The present study investigated the prevalence of depressive symptoms in older Koreans and identified associations between depressive symptoms and occupational factors. METHODS: Data from the Korean National Health and Nutrition Examination Survey V (2010–2012) were used to analyze 7320 participants aged 55 years or older. Complex sample logistic regression analysis was performed after adjusting general characteristics to determine associations between depressive symptoms and occupational factors. RESULTS: Among older Korean men, the prevalence of depressive symptoms in the employed and the non-employed groups were 9.9 % and 13.7 %, respectively. Employment status was significantly associated with depressive symptoms after adjusting for general factors (OR: 0.69, 95 % CI: 0.49–0.97). Among older Korean women, the prevalence of depressive symptoms in the employed and the non-employed groups were 17.4 % and 20.3 %, respectively, but employment status was not significantly associated with depressive symptoms. Second skill level occupational groups (clerks, plant and machine operators) in particular showed significantly lower prevalence of depressive symptoms than the non-employed group of men (9.3 % vs 13.7 %). By occupation type, the odds ratios were 0.31 (95 % CI: 0.10–0.97, clerks) and 0.47 (95 % CI: 0.23–0.86, plant and machine operators) adjusting for general factors. CONCLUSIONS: The employed group showed lower late-life depressive symptom prevalence than the non-employed group among older Korean men. In addition some second skill level occupations (clerks, plant and machine operators) were significantly associated with a lower risk of depressive symptoms after adjusting for general factors in older Korean men.

Association between long working hours and serum gamma-glutamyltransferase levels in female workers: data from the fifth Korean National Health and Nutrition Examination Survey (2010-2011)

OBJECTIVES: The present study investigated the association between long working hours and serum gamma-glutamyltransferase (GGT) levels, a factor influencing the incidence of cardiovascular disease. METHODS: Data from the fifth Korean National Health and Nutrition Examination Survey (2010-2011) were used to analyze 1,809 women. Subjects were divided into three groups based on the number of weekly working hours: or =52 hours per week. Complex samples logistic regression was performed after adjusting for general and occupational factors to determine the association between long working hours and high serum GGT levels. RESULTS: The prevalence of high serum GGT levels in groups with or =52 working hours per week was 22.0%, 16.9%, and 26.6%, respectively. Even after adjusting for general and occupational factors, those working 30-51 hours per week had the lowest prevalence of high serum GGT levels. Compared to those working 30-51 hours per week, the odds ratios (OR) of having high serum GGT levels in the groups with > or =52 and < or =29 working hours per week were 1.56 (95% confidence interval [CI], 1.10-2.23) and 1.53 (95% CI, 1.05-2.24), respectively. CONCLUSIONS: Long working hours were significantly associated with high serum GGT levels in Korean women.

Regional prevalence of non-alcoholic fatty liver disease in Seoul and Gyeonggi-do, Korea

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.

Intramucosal Colon Cancer Developing in an Inverted Hyperplastic Polyp

No abstract available.

Lipoic Acid Prevents the Changes of Intracellular Lipid Partitioning by Free Fatty Acid

BACKGROUND/AIMS: It is suggested that the hepatic lipid composition is more important than lipid quantity in the pathogenesis of non-alcoholic steatohepatitis. We examined whether lipoic acid (LA) could alter intrahepatic lipid composition and free cholesterol distribution. METHODS: HepG2 cells were cultured with palmitic acid (PA) with and without LA. Apoptosis, changes of the mitochondrial structure, intracellular lipid partitioning, and reactive oxygen species (ROS) activity were measured. RESULTS: Free fatty acid (FA) increased apoptosis, and LA co-treatment prevented this lipotoxicity (apoptosis in controls vs PA vs PA+LA, 0.5% vs 19.5% vs 1.6%, p<0.05). LA also restored the intracellular mitochondrial DNA copy number (553+/-33.8 copies vs 291+/-14.55 copies vs 421+/-21.05 copies, p<0.05) and reversed the morphological changes induced by PA. In addition, ROS was increased in response to PA and was decreased in response to LA co-treatment (41,382 relative fluorescence unit [RFU] vs 43,646 RFU vs 41,935 RFU, p<0.05). LA co-treatment increased the monounsaturated and polyunsaturated FA concentrations and decreased the total saturated FA fraction. It also prevented the movement of intracellular free cholesterol from the cell membrane to the cytoplasm. CONCLUSIONS: LA opposes free FA-generated lipotoxicity by altering the intracellular lipid composition and free cholesterol distribution.

A Study of Psychosocial Stress of Residents Near Asbestos Mines / 대한산업의학회지

OBJECTIVES: The purpose of this study is to identify the level of psychosocial stress of residents near asbestos mines, and to investigate the relationship between psychosocial stress and asbestos exposure history as well as, asbestos exposure awareness. METHODS: The survey was conducted in 297 individuals, by one-on-one interviews with a standard questionnaire including demographic characteristics, health status, asbestos exposure history, and awareness of asbestos exposure. The levels of psychosocial stress were measured through the Psychosocial Wellbeing Index-Short Form(PWI-SF). Multivariate logistic regression was conducted using psychosocial stress as a dependent variable. Demographic characteristics, health status, asbestos exposure history, and asbestos exposure awareness were examined as independent variable. RESULTS: The average PWI-SF score was 17.5 +/- 8.0, with 40 people (13.5%) in the high-risk stress group (PWI-SF 27 points or more). The group having an asbestos-related occupational history had a 2.53 times higher proportion of psychosocial stress (95% CI: 1.03~6.21). The group recognizing asbestos exposure had an even higher proportion of high psychosocial stress group (4.84 times, 95% CI: 1.41~16.55). CONCLUSIONS: The incidence of psychosocial stress is significantly higher in residents near asbestos mines having an asbestos-related occupational history who recognize their frequent asbestos exposure. Therefore, mental health is affected by the awareness of environmental asbestos exposure as well as an occupational exposure to asbestos.

The Prevalence of Asbestos Related Pleural Plaque among Residents Living Near Asbestos Mines in Korea / 대한산업의학회지

OBJECTIVES: The investigation of the prevalence of pleural diseases in regards to those living within 1 km of 14 asbestos mines in Chungnam province. METHODS: We enrolled 4,057 residents (male: 1,887, female: 2,170) living within 1km of asbestos mines in Chungcheong province. They received checkups from Soonchunhyang Environmental Health Center for asbestos related diseases between March 2009 and December 2009. Chest X-rays were taken from all subjects and read by two experts according to International Labor Organization guidelines. Those subjects suspected of asbestos related lesions were further checked with HRCT(high-resolution computed tomography). The determination was done by two experts after reviewing the resulting data. RESULTS: The 4,057 exposed residents underwent the checkup, 859 of whom further underwent the HRCT(high-resolution computed tomography) check. The prevalence of pleural plaque was found to be 11.3% (29.2% non-occupational, 8.0% occupational) from the chest X-rays. The HRCT(high-resolution computed tomography) results revealed that 227 subjects (26.4%) out of the 859 positive subjects (110 (18.8%) non-occupational, 117 (42.9%) occupational) showed evidence of pleural plaque. The statistical analysis showed that the prevalence of pleural plaque increased with increases in age, residence time, and occupational family exposure to asbestos (p<0.05). CONCLUSIONS: We recommend better control of asbestos in the soil and mines. We also recommend that all affected residents living near asbestos mines receive medical checkups as mandated by the asbestos health damage relief policy.

Acquired Dyschromatopsia among Workers Exposed to Acetone and Isopropyl Alcohol (IPA) / 대한산업의학회지

OBJECTIVES: The purpose of this study was to examine the correlation between exposure to acetone and isopropyl alcohol (IPA) and the acquisition dyschromatopsia. METHODS: A study was performed on exposure group of 116 people exposed to and a group of 36 people not exposed to organic solvents were selected and examined. Their smoking and alcohol habits, symptoms, and exposure history were surveyed through questionnaires and interviews. Then dyschromatopsia was evaluated with the Lanthony D-15 d test in a room with standardized intensity of illumination. RESULTS: The statistical prevalence of dyschromatopsia was significantly higher in the exposed group (30.2%) compared to that found in the control group (19.4%). Out of the 116 subjects in the exposed group, 30 people had acquired dyschromatopsia (25.86%). The variables affecting the color confusion index, such as age, exposure, and the duration of exposure, were statistically significant variables. CONCLUSIONS: He prevalence of dyschromatopsia was found to be not significantly higher in the group with exposure to organic solvents compared to that found in the control group. In addition, a statistically significant correlation was found between exposure to organic solvents and the color confusion index.

Validity of 38 mg Low Dose 13C-Urea Breath Test for the Diagnosis of Helicobacter pylori Infection

BACKGROUND: To assess the diagnostic value of 13C-UBT using capsulated 38 mg low dose for H. pylori infection, we investigated the sensitivity and specificity of 13C-UBT and to suggest the optimal positive cut-off value of DOB20 in 13C-UBT using ROC analysis. METHODS: The study subjects were 76 healthy individuals (males; 52, females; 24) who visited a health promotion center at a university hospital between July 2005 and June 2007. We tested for H. pylori infection by 38 mg low dose 13C-UBT and histology. We measured the expiratory 13C-urea concentration of basal and 20 minutes value after oral ingestion of 38 mg 13C- labelled urea with capsulated. The breath samples were analysed by gas chromatograph isotope ratio mass spectrometer and expressed as units of delta. RESULTS: Fifty subjects (65.8%) were H. pylori positive as judged from histology. ROC analysis showed an area under the curve (AUC) of 0.943 (95% confidence interval: 0.891~0.995), indicating an excellent classification performance of the model. The sensitivity of 96%, specificity of 85% were achieved at the optimal cut-off value of DOB20 which was 1.39. The 38 mg low dose 13C-UBT was a non-invasive, simple, short-time required and highly accurate method. CONCLUSION: The results suggested that capsulated 38 mg low dose 13C-UBT is considered more in term of accuracy, costeffectiveness and convenient method for the diagnosis of H. pylori infection. Further long-term research and meta analysis based on large-scale investigations is needed to establish a standardized testing method in creating protocol of 13C-UBT.

Erratum: The usefulness of ischemia modified albumin as an early ischemic marker to detect coronary artery disease in patients with chest pain presenting to the emergency department / 대한내과학회지

No abstract available.