Job strain is a major concern in view of its effects among civil servants associated with job burnout, mental fatigue and chronic diseases. The objective of this study was to assess the job strain level among civil servants and examine the effect of job strain on job burnout, mental fatigue and the resulting chronic diseases. A cross-sectional study with a representative sample consisting of 5000 civil servants was conducted from March to August 2014. Using a structured questionnaire, the job strain level, job burnout and mental fatigue were measured by using the Personal Strain Questionnaire (PSQ), Maslach Burnout Inventory (MBI) and Multidimensional Fatigue Inventory (MFI-20), respectively. Overall, 33.8% of the civil servants were found to be afflicted with high and moderate job strain. The characteristics of most of the civil servants with a higher-job strain level were as follows: female, Uygur, lower educational level and job title rank, shorter working experience, married marital status, and lower income level. Civil servants suffering from chronic disease mainly had hypertension and coronary heart disease, which accounted for 18.5% of the diseases. Civil servants with a high-job strain level exhibited higher rates of burnout, mental fatigue scores and incidence of chronic diseases. There was a multiple linear regression model composed of three predictor variables in job burnout, which accounted for 45.0% of its occurrence: female gender, lower-income level, higher-job strain in civil servants, the greater the rate of job burnout was. Four factors—male gender, lower-job title rank, higher-job strain, shorter-job tenure of civil servants—explained 25.0% of the mental fatigue model. Binary logistic regression showed that intermediate-rank employees (OR = 0.442, 95% CI: 0.028–0.634; p < 0.05), job tenure of 10–20 years (OR = 0.632, 95% CI: 0.359–0.989; p < 0.05), and low-job strain (OR = 0.657, 95% CI: 0.052–0.698; p < 0.05) were all associated with significantly lower odds of chronic disease. The risk of chronic disease was higher in civil servants with high-job burnout scores and mental fatigue scores compared with civil servants with lower scores (OR = 1.139, 95% CI: 1.012–3.198; OR = 1.697, 95% CI: 1.097–2.962). These data provide evidence for the effects of job strain on job burnout, mental fatigue and chronic diseases among civil servants.

It is debatable whether or not glucocorticoid receptor (GR) polymorphisms moderate susceptibility to PTSD. Our objective was to examine the effects of stressful life events, social support, GR genotypes, and gene-environment interactions on the etiology of PTSD. Three tag single nucleotide polymorphisms, trauma events, stressful life events, and social support were assessed in 460 patients with PTSD and 1158 control subjects from a Chinese Han population. Gene–environment interactions were analyzed by generalized multifactor dimensionality reduction (GMDR). Variation in GR at rs41423247 and rs258747, stressful life events, social support, and the number of traumatic events were each separately associated with the risk for PTSD. A gene–environment interaction among the polymorphisms, rs41423247 and rs258747, the number of traumatic events, stressful life events, and social support resulted in an increased risk for PTSD. High-risk individuals (a large number of traumatic events, G allele of rs258747 and rs41423247, high level stressful life events, and low social support) had a 3.26-fold increased risk of developing PTSD compared to low-risk individuals. The association was statistically significant in the sub-groups with and without childhood trauma. Our data support the notion that stressful life events, the number of trauma events, and social support may play a contributing role in the risk for PTSD by interacting with GR gene polymorphisms.

Objective: The present study was designed to demonstrate the relationships among shift work, hair cortisol concentration (HCC) and sleep disorders. Design: A cross-sectional study. Setting: Three petroleum administrations in Karamay city of Xinjiang, China. Participants: 435 individuals including 164 males and 271 females participated in the research. Outcome measures: Information on shift work was collected by a self-administered questionnaire. HCC was determined using an automatic radioimmunoassay instrument. Sleep quality was measured on the Pittsburgh Sleep Quality Index scale. Results: Shiftwork was associated with an increased prevalence of sleep disorders compared with the fixed day shift (two shifts: OR 3.11, 95% CI 1.57 to 6.19; three shifts: OR 2.87, 95% CI 1.38 to 5.98; four shifts: OR 2.22, 95% CI 1.17 to 4.18; others: OR 3.88, 95% CI= 1.36 to 11.08). Workers with different shift patterns had higher HCC levels than day workers ((fixed day shift: geometric mean±geometric SD=2.33±1.65; two shifts: 3.76±1.47; three shifts: 3.15±1.64; four shifts: 3.81±1.55; others: 3.60±1.33) ng/g hair, η ² =0.174) and high HCC was associated with the higher prevalence of sleep disorders (OR 4.46, 95% CI 2.70 to 7.35). The mediating effect of HCC on the relationship between shift work and sleep disorders was 0.25 (95% CI 0.09 to 0.41). Conclusion: We found that, when compared with the fixed day shift, shiftwork was associated with both the higher HCC, and also with an increased risk of sleep disorders. High HCC was associated with the occurrence of sleep disorders. In addition, HCC had mediating effect in shift work and sleep disorders. Thus, HCC can be considered as an early marker of shiftwork circadian disruption to early detection and management of sleep disorders.

The serotonin receptor (5-HTR) plays a key role in sleep quality regulation. Job-related stress is an important factor that influences sleep quality. However, few reports on the interaction between 5-HTR2A polymorphisms and job stress, and how they may impact upon sleep quality are available. Therefore this study investigated the effects of job stress, 5-HTR2A polymorphisms, and their interaction on sleep quality, in physicians. Using a two-stage stratified sampling method, 918 participants were initially invited to participate in the study. After screening for study inclusion and exclusion criteria, 504 subjects were eventually included in the study. Job stress and sleep quality were assessed using the Job Stress Survey (JSS) and Pittsburgh Sleep Quality Index (PSQI), respectively. The 5-HTR2A receptor gene polymorphisms T102C and -1438G/A of were determined using polymerase chain reaction-restriction fragment length polymorphism. Job stress was significantly associated with sleep quality. High levels of job stress were linked to a higher risk of poor sleep quality compared to low or moderate levels [odds ratio (OR) = 2.909, 95% confidence interval (CI): 1.697–4.986]. High levels of stress may reduce subjects’ sleep quality, leading to an increase the likelihood of sleep disturbances and subsequent daytime dysfunction. The 5-HTR2A receptor gene polymorphism T102C was not significantly associated with sleep quality in this study, however, the -1438G/A polymorphism was significantly associated with sleep quality. The GG genotype of the -1438G/A polymorphism was linked to poorer sleep quality. When compared with subjects with low job-related stress levels×AG/AA genotype (OR = 2.106, 95% CI: 1.278–3.471), physicians with high job-related stress levels×GG genotype had a higher risk of experiencing poor sleep quality (OR = 13.400, 95% CI: 3.143–57.137). The findings of our study indicate that job stress and 5-HTR2A receptor gene polymorphisms are associated with sleep quality in physicians. Subjects with high job stress level or/and the -1438G/A GG genotype were more likely to report poor sleep quality, and furthermore, their combination effect on sleep quality was higher than their independent effects, so it may be suggested that job-related stress and genes have a cumulative effect on sleep quality; that is, stress can increase the risk of poor sleep quality, but this effect is worse in a group of people with specific gene polymorphisms.