Shin-Goo Park

Association between Job Stress and Insomnia in Korean Workers

Association between Job Stress and Insomnia in Korean Workers: Hwan‐Cheol Kim, et al. Department of Occupational and Environmental Medicine, Inha University Hospital, Korea—

Precarious employment and the risk of suicidal ideation and suicide attempts

OBJECTIVE Although the effect of occupation or employment status on suicide risk is notable, there are few studies on the effect of precarious employment on suicide. We compared suicidal ideation and suicide attempts in precarious workers and their non-precarious counterparts using a representative sample from South Korea. METHOD The 2008 Korean Community Health Survey data were used for this study. Information was obtained on 52,161 participants (41,063 employees with non-precarious work and 11,098 employees with precarious work). The outcome of the logistic regression model was the presence of suicidal thoughts and attempts, and the independent variables were the demographics, socioeconomic status, and health status. RESULTS Employees with precarious work were more likely to exhibit suicidal ideation (OR=1.41; 95% CI, 1.28-1.55) and suicide attempts (OR=1.52; 95% CI, 1.02-2.27) than employees with non-precarious work. After controlling for income and education (Model 2) depressive feelings (Model 6), compared with unadjusted model, remained significant but the odds ratio was largely attenuated, indicating a strong association between suicidal risk and socioeconomic and feelings of depression. CONCLUSION Precarious workers had a higher risk of suicidal ideation and suicide attempts than non-precarious workers. Our study suggests that precarious employment is an important risk for suicide.

Association among Working Hours, Occupational Stress, and Presenteeism among Wage Workers: Results from the Second Korean Working Conditions Survey

ObjectivesThe purpose of the present study was to identify the association between presenteeism and long working hours, shiftwork, and occupational stress using representative national survey data on Korean workers.MethodsWe analyzed data from the second Korean Working Conditions Survey (KWCS), which was conducted in 2010, in which a total of 6,220 wage workers were analyzed. The study population included the economically active population aged above 15 years, and living in the Republic of Korea. We used the chi-squared test and multivariate logistic regression to test the statistical association between presenteeism and working hours, shiftwork, and occupational stress.ResultsApproximately 19% of the workers experienced presenteeism during the previous 12 months. Women had higher rates of presenteeism than men. We found a statistically significant dose–response relationship between working hours and presenteeism. Shift workers had a slightly higher rate of presenteeism than non-shift workers, but the difference was not statistically significant. Occupational stress, such as high job demand, lack of rewards, and inadequate social support, had a significant association with presenteeism.ConclusionsThe present study suggests that long working hours and occupational stress are significantly related to presenteeism.

Working Hours and Cardiovascular Disease in Korean Workers: A Case-control Study

Working Hours and Cardiovascular Disease in Korean Workers: A Case‐control Study: Inchul JEONG, et al. Graduate School of Public Health, Yonsei University, Republic of Korea—

Digital thermography of the fingers and toes in Raynaud's phenomenon.

The aim of this study was to determine whether skin temperature measurement by digital thermography on hands and feet is useful for diagnosis of Raynauds phenomenon (RP). Fifty-seven patients with RP (primary RP, n = 33; secondary RP, n = 24) and 146 healthy volunteers were recruited. After acclimation to room temperature for 30 min, thermal imaging of palmar aspect of hands and dorsal aspect of feet were taken. Temperature differences between palm (center) and the coolest finger and temperature differences between foot dorsum (center) and first toe significantly differed between patients and controls. The area under curve analysis showed that temperature difference of the coolest finger (cutoff value: 2.2℃) differentiated RP patients from controls (sensitivity/specificity: 67/60%, respectively). Temperature differences of first toe (cutoff value: 3.11℃) also discriminated RP patients (sensitivity/specificity: about 73/66%, respectively). A combination of thermographic assessment of the coolest finger and first toe was highly effective in men (sensitivity/specificity : about 88/60%, respectively) while thermographic assessment of first toe was solely sufficient for women (sensitivity/specificity: about 74/68%, respectively). Thermographic assessment of the coolest finger and first toe is useful for diagnosing RP. In women, thermography of first toe is highly recommended. Graphical Abstract

Long Working Hours and Emotional Well-Being in Korean Manufacturing Industry Employees

ObjectivesKorea is well known for its long work hours amongst employees. Because workers of the manufacturing industry are constantly exposed to extended work hours, this study was based on how long work hours affect their emotional well-being.MethodsThe analysis was done using the secondary Korean Working Condition Survey (KWCS). Long work hours were defined to be more than 48 hours, and they were subcategorized into units of 52 hours and 60 hours. Based on the WHO (five) well-being index, emotional state was subdivided into three groups - reference group, low-mood group, and possible depression group- where 28 points and 50 points were division points, and two groups were compared at a time. Association between long work hours and emotional state was analyzed using binary and multinomial logistic regression analysis.ResultsWorking for extended working hours in the manufacturing industry showed a statistically significant increase (t test p < 0.001) in trend among the possible depression group when compared to the reference group and the low-mood group. When demographical characteristics, health behaviors, socioeconomic state, and work-related characteristics were fixed as controlled variables, as work hours increased the odds ratio of the possible depression group increased compared to the reference group, and especially the odds ratio was 2.73 times increased for work hours between 48–52 and 4.09 times increased for 60 hours or more and both were statistically significant. In comparing the low-mood group and possible depression group, as work hours increased the odds ratio increased to 1.73, 2.39, and 4.16 times, and all work hours from working 48–52 hours, 53–60 hours, and 60 hours or more were statistically significant. Multinomial logistic regression analysis also showed that among the reference group and possible group, the possible depression group was statistically significant as odds ratio increased to 2.94 times in working 53–60 hours, and 4.35 times in 60 hours or more.ConclusionsLong work hours have an adverse effect on emotional well-being. A more diversified research towards variables that affect long work hours and emotional well-being and how they interact with each other and their relationship to overall health is imperative.

Treatment of CFRP by IAR method and its effect on the fracture behavior of adhesive bonded CFRP/aluminum composites

Abstract It was shown in the previous studies that adhesive shear strength of carbon fiber reinforced plastics (CFRP) to aluminum composites could be improved by the surface treatment of CFRP using Ar + ion irradiation. In the present work, the effect of CFRP treatment by Ar + ion irradiation on the fracture behavior of CFRP/aluminum joint was studied. The aluminum used was 7075-T6 and the CFRP used was multi-directional graphite/epoxy composites whose stacking sequence was [0°/±45°/0°] 3s . The surface of CFRP was treated using Ar + ion irradiation in an oxygen environment. The Ar + ion dose used was 1×10 16 ions cm −2 . Fracture toughness of CFRP/aluminum joint was determined from cracked lap shear specimens using work factor approach. Then, the fracture toughness of ion beam-treated CFRP/aluminum joint was compared with that of untreated CFRP/aluminum joint. The results showed that the fracture toughness of ion beam-treated CFRP/aluminum case was about 72% higher than that of untreated CFRP/aluminum case. X-ray photoelectron spectrometer analysis showed that intensity of hydrophilic bonds, CO (carbonyl group) and OCO (carboxyl group) was increased by the Ar + ion-irradiation in an oxygen environment. Scanning electron microscope examination showed that cohesive failure occurred for ion beam-treated CFRP/aluminum joint while adhesive failure occurred for untreated CFRP/aluminum joint.

Early effects of tumor necrosis factor inhibition on bone homeostasis after soluble tumor necrosis factor receptor use

Background/Aims Our aim was to assess whether short-term treatment with soluble tumor necrosis factor (TNF) receptor affects circulating markers of bone metabolism in rheumatoid arthritis (RA) patients. Methods Thirty-three active RA patients, treated with oral disease-modifying antirheumatic drugs (DMARDs) and glucocorticoids for > 6 months, were administered etanercept for 12 weeks. Serum levels of bone metabolism markers were compared among patients treated with DMARDs at baseline and after etanercept treatment, normal controls and naive RA patients not previously treated with DMARDs (both age- and gender-matched). Results Bone-specific alkaline phosphatase (BSALP) and serum c-telopeptide (CTX)-1 levels were lower in RA patients treated with DMARDs than in DMARD-naive RA patients. After 12 weeks of etanercept treatment, serum CTX-1 and sclerostin levels increased. In patients whose DAS28 improved, the sclerostin level increased from 1.67 ± 2.12 pg/mL at baseline to 2.51 ± 3.03 pg/mL, which was statistically significant (p = 0.021). Increases in sclerostin levels after etanercept treatment were positively correlated with those of serum CTX-1 (r = 0.775), as were those of BSALP (r = 0.755). Conclusions RA patients treated with DMARDs showed depressed bone metabolism compared to naive RA patients. Increases in serum CTX-1 and sclerostin levels after short-term etanercept treatment suggest reconstitution of bone metabolism homeostasis.

Workplace injustice and self-reported disease and absenteeism in South Korea.

BACKGROUND This study investigated whether experience of workplace injustice was associated with self-reported occupational health using a nationally representative sample of Korean workers. METHODS We used the first wave of the Korean Working Conditions Survey (KWCS) and included 7,007 wage employees as the study population. Workplace injustice included the experience of discrimination, violence, or harassment, and occupational health was measured as self-reported health problems and absenteeism. Personal, occupational, and job-related characteristics were included as covariates. RESULTS An average of 7.2% of workers reported experiencing at least one workplace injustice over the past 12 months. Female workers were significantly more likely to experience age and gender discrimination, and unwanted sexual attention than male workers. Both male and female workers who experienced any workplace injustice (i.e., discrimination, harassment, or violence) reported approximately two- to threefold increased risk for physical and mental health problems (i.e., backaches, muscular pain, stomach pain, overall fatigue, headaches, anxiety/depression, sleeping problems, and injury) and absenteeism due to accidents or due to health problems. CONCLUSION Perceived injustice at work was significantly associated with an increased risk of occupational disease and absenteeism for Korean wage employees.

Hydrogen Sulfide Intoxication with Dilated Cardiomyopathy

Hydrogen sulfide (H 2 S) is a colorless, heavier-than-air, inflammable, highly toxic irritant and chemical asphyxiant gas, which has a characteristic rotten-egg odor that is detectable at concentrations as low as 0.5 ppb, but this warning property may be lost in 2 to 15 min at concentrations over 100 ppm through olfactory fatigue . Hydrogen sulfide is generated naturally by decaying sulfur-containing proteins and is released from sewage sludge, liquid manure, sulfur hot springs, and natural gas. It is also a by-product of many industrial processes, including petroleum refining, sewage disposal, mining, wood pulp processing, rayon manufacturing, manure processing, sugar-beet processing, fish processing and hot-asphalt paving . Hydrogen sulfide is especially risky in confined spaces such as fishing-ship holders, manure pits, and sewers. In the United States, 52 deaths related to hydrogen sulfide were reported from 1993 to 1999 in various industries. The toxic mechanism of hydrogen sulfide comprises inactivating cytochrome oxidase in mitochondria and then preventing the cellular metabolism of oxygen. Via this mechanism, hydrogen sulfide can induce hypoxic brain damage and hypoxic cardiac damage as well as mucosal irritation and pulmonary edema. Nevertheless, few cases of cardiac damage following hydrogen sulfide exposure have been reported. We here report a case of dilated cardiomyopathy after hydrogen sulfide inhalation in a sewer worker, the first case report of dilated cardiomyopathy caused by hydrogen sulfide. Case Presentation