Circadian misalignment and sleep disruption i̇n shift work: a bidirectional model of mental health risk

Background:

Occupational health has the responsibility of protecting and improving workers’ health proactively. It is known that shift work is associated with significant disturbances in sleep and circadian rhythms for a long time as an occupational health problem. Growing evidence suggests that circadian misalignment and sleep disruption may interact bidirectionally, forming a vicious cycle that adversely affects each other and mental health. However, this dynamic interplay remains insufficiently conceptualized within occupational health literature. 2-5 % of people who work in shift works have sleep disorder. Although various pharmacological and non-pharmacological solutions are suggested to address the problem, they can all disrupt sleep patterns and lead to different health problems in the long term. When shift workers are employee of sectors critical to human health, the issue should also be addressed as a significant public health problem. To develop a solution, first of all the vicious cycle created by shift work should be understood and each etiological factor should be handled as a root cause in terms of occupational health because the issue is an workplace problem and may be solved in this approach.

Objective:

This review aims to examine the bidirectional relationship between shift work, sleep disruption, and circadian rhythm misalignment, and to explore how this vicious cycle contributes to adverse mental health outcomes so that to be a gate for solution.

Methods:

A narrative review will be presented using literature of sleep, circadian rhythm and occupational health from PubMed, Scopus, and Google Scholar Keywords such as “shift work”, “circadian rhythm”, “sleep disturbance”, and “mental health” were used. Studies published in English within the last two decades were prioritized, with relevant studies those are landmark for the issue in an occupational safety and health approach.

Results:

Evidence especially from occupational health literature indicates that while circadian rhtym and sleep works in a feedback shift work disturbs both of them and exists a vicious cycle which impairs emotional regulation, cognitive function, and stress resilience. Those results are associated with increased risks of depression, anxiety, and burnout. Neurobiological mechanisms involve dysregulation of melatonin secretion, hypothalamic–pituitary–adrenal (HPA) axis activation, and alterations in neurotransmitter systems. Importantly, impaired mental health further exacerbates sleep disturbances, reinforcing the vicious cycle too.

Conclusions:

Occupational health dicipline should be include all the haelth problems of workplaces while protecting and improving workers’ health. The interaction between shift work, sleep disruption, and circadian misalignment represents a critical pathway influencing mental health as an occupational healt issue. Understanding this cycle may inform targeted interventions, including chronotherapeutic strategies and workplace policy adjustments, to mitigate mental health risks among shift workers. With this review a conceptual vicious cycle model integrating circadian, sleep and mental health pathways will be proposed in occupational safety and health approach by the related medical diciplines.

References

No references: they will be presented in the poster.