Work-Related Psychosocial Factors and Global Cognitive Function: Are Telomere Length and Low-Grade Inflammation Potential Mediators of This Association?

The identification of modifiable factors that could maintain cognitive function is a public health priority. It is thought that some work-related psychosocial factors help developing cognitive reserve through high intellectual complexity. However, they also have well-known adverse health effects and are considered to be chronic psychosocial stressors. Indeed, these stressors could increase low-grade inflammation and promote oxidative stress associated with accelerated telomere shortening. Both low-grade inflammation and shorter telomeres have been associated with a cognitive decline. This study aimed to evaluate the total, direct, and indirect effects of work-related psychosocial factors on global cognitive function overall and by sex, through telomere length and an inflammatory index. A random sample of 2219 participants followed over 17 years was included in this study, with blood samples and data with cognitive function drawn from a longitudinal study of 9188 white-collar workers (51% female). Work-related psychosocial factors were evaluated according to the Demand-Control-Support and the Effort-Reward Imbalance (ERI) models. Global cognitive function was evaluated with the validated Montreal Cognitive Assessment (MoCA). Telomere length and inflammatory biomarkers were measured using standardised protocols. The direct and indirect effects were estimated using a novel mediation analysis method developed for multiple correlated mediators. Associations were observed between passive work or low job control, and shorter telomeres among females, and between low social support at work, ERI or iso-strain, and a higher inflammatory index among males. An association was observed with higher cognitive performance for longer telomeres, but not for the inflammatory index. Passive work overall, and low reward were associated with lower cognitive performance in males; whereas, high psychological demand in both males and females and high job strain in females were associated with a higher cognitive performance. However, none of these associations were mediated by telomere length or the inflammatory index. This study suggests that some work-related psychosocial factors could be associated with shorter telomeres and low-grade inflammation, but these associations do not explain the relationship between work-related psychosocial factors and global cognitive function. A better understanding of the biological pathways, by which these factors affect cognitive function, could guide future preventive strategies to maintain cognitive function and promote healthy aging.

Self-rated health (SRH), recovery from work, fatigue, and insomnia among commercial pilots concerning occupational and non-occupational factors

Background

This study investigated associations of self-rated health (SRH), recovery from work, fatigue, and insomnia with working conditions, the psychosocial work environment, lifestyle, and sense of coherence (SOC) among commercial pilots.

Methods

A standardized questionnaire was sent to all pilots in an airline company, of whom 354 (61%) responded. Associations were analyzed via ordinal and logistic regression with mutual adjustment.

Results

Overall, 21.8% of participants reported low SRH, 13.0% reported not recovering from work during their free time, 61.9% experienced fatigue, and 70.6% experienced insomnia symptoms. A high level of demand at work was associated with poor SRH and more fatigue, and low social support at work was associated with insomnia and poorer recovery from work. Habits surrounding exercise and BMI were associated with SRH. Part-time pilots and captains reported experiencing better recovery from work than their counterparts, while female pilots and younger pilots reported less fatigue. Amount of free time after work and the type of airplane operated were associated with experience of insomnia symptoms. Finally, having a strong sense of coherence was protectively associated with all health outcomes.

Conclusion

The psychosocial environment at work is essential for the health of pilots, and a strong sense of coherence can be protective. Occupational conditions may influence recovery from work, fatigue, and insomnia. Moreover, engaging in exercise, maintaining a healthy weight, working part-time, and having more free time after the working day could improve pilots' health.