Association of effort-reward imbalance and insomnia in steel workers: a structural equation modeling analysis / 中国职业医学

OBJECTIVE: To explore the relationship between Effort-Reward Imbalance(ERI) and insomnia using structural equation modeling. METHODS: A total of 5 769 steel workers from an iron and steel company were selected as study objects by convenient sampling method. The Effort-Reward Imbalance Scale and Five-Item Athens Insomnia Scale were used to investigate their ERI and insomnia respectively. A structural equation modeling was constructed to analyze the relationship between ERI and insomnia. RESULTS: The scores of work effort and internal investment were positively correlated with the score of insomnia [the Spearman correlation coefficient(r_S) were 0.127 and 0.122 respectively, P<0.01]. Work reward scores were negatively correlated with the score of insomnia(r_S=-0.126, P<0.01). We successfully construct a structural equation model between ERI and insomnia in steel workers. According to this model, work effort, work reward and internal investment had direct effect on insomnia [the standardized path coefficient(β) were 0.065,-0.067 and 0.091 respectively, P<0.05]. Work effort and work reward have direct effect on insomnia(the β were 0.048 and-0.010 respectively, P<0.05). CONCLUSION: ERI increases the risk of insomnia. Both effort and internal investment have positive effect on insomnia, while reward has negative effect on insomnia.

Dose-response relationship between light at night and nonalcoholic fatty liver in steel workers / 中华疾病控制杂志

Objective To explore the relationship between light at night (LAN) and nonalcoholic fatty liver (NAFLD) in steel workers. Methods Relevant information was collected through questionnaires, physical examinations and blood biochemical analysis. Using restricted cubic spline (RCS) and mutiple Logistic regression model to explore the relationship between LAN and NAFLD based on a cross-sectional study. Results The prevalence of NAFLD was 33.8% (2 594 / 7 664) in steel workers. After adjusting for age, sex, marriage, educational level, smoking, drinking, body mass index, luminous intensity in life, liver enzyme metabolism, blood lipid level, physical activity, diet, sleep duration, shift work, high temperature, noise, dust, and carbon monoxide exposure, the RCS model showed a nonlinear dose-response relationship between LAN and NAFLD ( 2=71.59, P<0.001 for overall association test and 2=16.92, P<0.001 for nonlinear test); Multivariate Logistic regression model showed that after adjusting for all confounding factors, when the LAN in the 1 178 d ~ 2 017 d and 2 017 d ~ group, the prevalence of NAFLD increased by 21.7% (OR=1.217, 95% CI: 1.027-1.441) and 47.9% (OR=1.479, 95% CI: 1.240-1.763), respectively, when compared with the group LAN<1 178 d. Conclusion There is a nonlinear dose-response relationship between LAN and NAFLD in steel works.

The Moderating and Mediating Roles of Psychological Capital in the Associations of Effort-reward Imbalance and Overcommitment with Job Burnout among Iron-steel Workers / 中国医科大学学报

Objective To explore the moderating and mediating roles of psychological capital in the associations of effort?reward imbalance and overcommitment with job burnout among iron?steel workers. Methods Totally 1 700 male iron?steel workers from an iron and steel company were enrolled for the study. A set of questionnaires that included demographic and working factors,the Maslach Burnout Inventory?General Survey,the Ef?fort?reward Imbalance Scale and the Psychological Capital Questionnaire,as well as perceived work environment was distributed to the subjects. A to?tal of 1 254 effective respondents(73.76%)were collected. Hierarchical linear regression analysis was performed to explore moderating role,and as?ymptotic and resampling strategies were used to detect mediating role. Results There was no moderating role of psychological capital on the associa?tion between effort?reward imbalance and job burnout. Psychological capital had significant and positive moderating roles on the associations of over?commitment with emotional exhaustion and cynicism. Psychological capital showed significant mediating role in the associations of effort?reward im?balance with emotional exhaustion and cynicism,and the proportion of mediating role was 5.84%and 18.75%,respectively. Conclusion In work?ers with high level of psychological capital,emotional exhaustion and cynicism would be significantly increased with overcommitment,and there is a weak increasing trend of emotional exhaustion and cynicism in workers with low level of psychological capital. Effort?reward imbalance could lead to emotional exhaustion and cynicism through the reduction of psychological capital of iron?steel workers.

Respiratory Symptoms And Pulmonary Function Among Male Steel Workers In Terengganu, Malaysia

A cross sectional study was carried out to determine the relationship between dust exposure and pulmonary function in male steel workers in Terengganu, Malaysia. The investigation included spirometric testing and detailed personal interviews using a structured questionnaire adopted from British Medical Research Council (BRMC) Questionnaire on respiratory symptoms. Respiratory symptoms commonly reported by the male workers were morning phlegm (33.1%), shortness of breath (31.9%), chest tightness (30.4%), and morning cough (17.8%). Age and duration of employment were among the factors associated with respiratory symptoms (p<0.05 and p<0.001 respectively). Forced Expiratory Volume in 1 second (FEV1) was significantly reduced when compared to the healthy population. There was a significant decrease of FEV1 between before and after work shift (t= 3.582, p<0.001). Smoking status, age, and duration of employment were also associated with reduction of pulmonary function (p<0.01).

Prevalence and correlation factors of carotid atherosclerosis among the middle and old aged workers in an Iron and Steel corporation, Chongqing / 中华流行病学杂志

Objective To investigate the prevalence and correlation factors of carotid atherosclerosis (CAS) among workers of Chongqing Iron and Steel Corporation, and to offer information for the development of prevention program for cerebro-vascular disease. Methods 512 asymptomatic individuals (mean age 56.8 years, ranged from 45 to 80) from the subsidiary workshop of Chongqing Iron and Steel Corporation were recruited. Demographic data and serum were collected and the internal-media thickness (IMT) of the CAS and the extent of plaque formation were evaluated by B-mode ultrasound. Logistic regression analysis was used to estimate the correlation factors of CAS. Results (1) The overall prevalence of carotid atherosclerosis among the iron and steel workers was 37.6%. IMT was found as 10.2% , with the prevalence rates of nonstenotic plaque and stenotic plaque were 25.0% and 2.4% respectively. (2)It was shown by logistic regression analysis that age (0R=1.289, 95%CI: 1.014-1.568, P<0.001 ), smoking (0R=1.420, 95%C1: 0.802-3.872, P<0.001 ), hypertension (0R=4.530, 95%CI: 3.952-6.753, P<0.001), diabetes mellitus (0R=2.285, 95%C1: 1.008-5.057, P<0.001 ), HsCRP(0R= 1.273, 95%C1: 0.479-2.889, P=0.037), TC (0R= 1.032,95%C1: 0.320-1.882,P=0.047) and LDL-C (0R=2.313, 95% CI:1.237-4.331, P=0.008) were significantly associated with the severity of CAS. (3)Prevalence of the CAS increased with the increasing number of correlation factors. Conclusion The prevalence of CAS among the iron and steel workers was higher than those in ordinary people of the same age. Age, smoking, hypertension, diabetes mellitus, HsCRP, TC and LDL-C were independent risk factors related to CAS. The prevalence of CAS was increasing parallel to the number of correlation factors.