Cross-Sectional Survey of Mental Health Risk Factors and Comparison of the Monoamine oxidase A Gene DNA Methylation Level in Different Mental Health Conditions among Oilfield Workers in Xinjiang, China

MAOA methylation is associated with impulsive and antisocial behaviour: dependence on allelic variation, family environment and diet

Congenital absence of monoamine oxidase A (MAO-A) activity predisposes to antisocial impulsive behaviour, and the MAOA uVNTR low-expressing genotype (MAOA-L) together with childhood maltreatment is associated with similar phenotypes in males. A possible explanation of how family environment may lead to such behaviour involves DNA methylation. We have assessed MAOA methylation and impulsive/antisocial behaviour in 121 males from the Estonian Children Personality Behaviour and Health Study. Of the 12 CpG sites measured, methylation levels at the locus designated CpG3 were significantly lower in subjects with antisocial behaviour involving police contact. CpG3 methylation was lower in subjects with alcohol use disorder by age 25, but only in MAOA-H genotype. No correlation between MAOA CpG3 methylation levels and adaptive impulsivity was found at age 15, but in MAOA-L genotype a positive correlation appeared by age 18. By age 25, this positive correlation was no longer observed in subjects with better family relationships but had increased further with experience of adversity within the family. MAOA CpG3 methylation had different developmental dynamics in relation to maladaptive impulsivity. At age 18, a positive correlation was observed in MAOA-L genotype with inferior family relationships and a negative correlation was found in MAOA-H with superior home environment; both of these associations had disappeared by age 25. CpG3 methylation was associated with dietary intake of several micronutrients, most notable was a negative correlation with the intake of zinc, but also with calcium, potassium and vitamin E; a positive correlation was found with intake of phosphorus. In conclusion, MAOA CpG3 methylation is related to both maladaptive and adaptive impulsivity in adolescence in MAOA-L males from adverse home environment. By young adulthood, this relationship with maladaptive impulsivity had disappeared but with adaptive impulsivity strengthened. Thus, MAOA CpG3 methylation may serve as a marker for adaptive developmental neuroplasticity in MAOA-L genotype. The mechanisms involved may include dietary factors.

US research needs related to fatigue, sleep, and working hours among oil and gas extraction workers

BACKGROUND

During 2003-2013, 1189 US oil and gas extraction (OGE) workers died while working, resulting in an average annual workplace fatality rate seven times that for all US workers. OGE work commonly involves long hours, shiftwork, irregular schedules, and long commutes, but effects of these factors on fatigue, occupational injury, and illness in OGE are largely unknown.

METHODS

A scoping review of relevant OGE research during 2000-2019 was completed and supplemented by input from a NIOSH-sponsored Forum.

RESULTS

Seventy-eight papers were identified; 76% reported only offshore research. Five themes for research needs emerged: build knowledge about the impacts of fatigue; explore interactions between on- and off-the-job risk factors; identify and evaluate interventions; assess effectiveness of technology; and increase the diffusion of fatigue risk management information.

CONCLUSIONS

Further collaboration between researchers and OGE operators and contractors can lead to action-oriented recommendations to mitigate the effects of fatigue, inadequate sleep, and shiftwork.

Research on the Effects of Occupational Stress and the DRD2 Gene on the Psychological Health of Workers in the Xinjiang Desert Oil Field

Background: This study investigated the relationship between occupational stress and the mental health of people working in oil fields in the arid desert environment of Xinjiang, and revealed the causal relationship between occupational stress and psychological disorders, while furthermore exploring the relationship between psychological disorders and genetic levels. Methods: The participants of this study included oil field company workers from the Xinjiang Petroleum Administration of Karamay City, Xinjiang, who underwent occupational health examinations. The Occupational Stress Inventory Revised Edition (OSI-R) was used to measure the occupational stress of the oil workers. The mental health status of oil workers was evaluated using the Symptoms Checklist-90. Results: Occupational tasks: The total scores of the personal strain and mental health questionnaires were positively correlated with somatization, obsessive-compulsive symptoms, interpersonal sensitivity, depression, anxiety, hostility, terror, paranoia, and psychosis (P < 0.05). Individual coping resources and the mental health total score was negatively correlated with somatization, obsessive-compulsive symptoms, interpersonal sensitivity, anxiety, hostility, terror, paranoia, and psychosis. The following factors were identified as mental health risk factors: female gender; age 45 and above (relative to ≤30 years old); high scores on the personal strain questionnaire; occupational stress; external effort; internal investment; and high effort-low return. The following factors were identified as protective factors for mental health: Han nationality; oil transportation (relative to drilling); individual resilience; and work returns. In respect to the abnormal psychological group and the normal psychological group, statistically significant differences were found in the distribution of genotypes and allele frequencies at the rs1800497 locus (P < 0.05). The depression and paranoia scores observed between different genotype groups at the rs1800497 locus were statistically significant (P < 0.05). Conclusions: This study shows that occupational stress and the D2 dopamine receptor (DRD2) gene have an impact on the mental health of oil field workers in the arid desert environment of Xinjiang. Effort-reward imbalance and occupational stress were identified as risk factors for mental health, while rewards for work were protective factors. Higher levels of occupational stress may lead to depression and other psychological disorders, adversely affecting mental health. In oil field operators in the arid desert environment of Xinjiang, the AA genotype of the DRD2 gene in the rs1800497 locus was identified as a genotype specific to susceptibility to mental health problems, and a correlation was found between the A allele and an increased risk of psychological problems. Therefore, it is necessary to devise relevant measures to alleviate occupational stress among oil workers and increase their job rewards, so as to improve their mental health.