Night-Time Shift Work and Related Stress Responses: A Study on Security Guards

Area of Science:

• Occupational Health
• Endocrinology
• Cardiovascular Physiology

Background:

• Work-related stress disrupts homeostasis via the hypothalamic-pituitary-adrenal axis and sympathetic nervous system.
• Night-shift work disrupts natural light-dark cycles and circadian rhythms, with unknown long-term health consequences.
• The impact of circadian rhythm disruption on disease pathogenesis, including cancer, requires further investigation.

Purpose of the Study:

• To investigate the relationship between job activities, stress responses, and physiological markers in security guards.
• To evaluate salivary cortisol levels and blood pressure as indicators of stress in night-shift workers.
• To understand the impact of night-shift work on circadian rhythm disruption and associated health risks.

Main Methods:

• Recruited ninety security guards, including night-time and daily-shift workers.
• Collected saliva samples from security guards at three time points: 22:00, 06:30, and 14:00.
• Measured salivary cortisol levels and blood pressure before and after work shifts.

Main Results:

• Observed significant alterations in cortisol levels during night shifts, with notable increases before and after work periods.
• Identified a physiological prevalence of vagal tone on cardiocirculatory activity during night-shift work.
• Demonstrated significant variations in cardiovascular parameters at the end of night shifts.

Conclusions:

• Cortisol levels and blood pressure serve as sensitive biomarkers for biological responses to severe occupational stress.
• Shift work, particularly night shifts, can lead to significant increases in cortisol and cardiovascular parameter variations.
• The findings underscore the physiological consequences of disrupted circadian rhythms due to night-shift work.