Harris Anette, Waage Siri, Ursin Holger, Eriksen Hege R
Research Center for Health Promotion, Faculty of Psychology, University of Bergen, N-5015, Bergen, Norway.
Int J Circumpolar Health. 2011;70(5):542-51. doi: 10.3402/ijch.v70i5.17857. Epub 2011 Oct 17.
The aim was to investigate how working in an extreme and isolated environment in the Arctic affected the diurnal rhythm of saliva cortisol.
Field study.
Twenty-five male tunnel workers were screened during 3 different working cycles with different light conditions during a 9-month construction period; April/May (24 hours [h] light), September/October (approximately 12 h light and 12 h darkness) and November/December (24 h darkness). The work schedule was 10 h on/14 h off, 21 days at work/21 days off work. The workers alternated between the day shift in 1 work period and the night shift in the next. Four saliva samples were collected on day 14 in all 3 periods; immediately after awakening, and then 30 minutes, 6 hours and 12 hours after awakening.
Regardless of shift schedule, the workers' cortisol levels were significantly lower in the period with 24 hours of light per day compared to the period with "normal" light conditions. There were no differences in the cortisol levels of the workers on night shifts in the period with 24 hours of darkness compared to those in the period with "normal" light conditions, but the workers who were on day shifts in the period with 24 of hours darkness had a disturbed cortisol rhythm (lower peak after awakening and lack of the normal decrease during the day).
External light conditions and shift schedule were important factors in regulating the workers' cortisol rhythm. It seems to be easier to adapt to a night rhythm than an early morning rhythm in an isolated and extreme environment.
本研究旨在调查在北极极端且与世隔绝的环境中工作如何影响唾液皮质醇的昼夜节律。
实地研究。
在为期9个月的施工期间，对25名男性隧道工人在3个不同的工作周期进行筛查，这些周期的光照条件不同；4月/5月（24小时光照）、9月/10月（约12小时光照和12小时黑暗）以及11月/12月（24小时黑暗）。工作安排为工作10小时/休息14小时，工作21天/休息21天。工人们在一个工作周期上白班，在下一个周期上夜班。在所有3个周期的第14天采集4份唾液样本；醒来后立即采集，然后在醒来后30分钟、6小时和12小时采集。
无论轮班安排如何，与“正常”光照条件的时期相比，工人们在每天24小时光照的时期皮质醇水平显著降低。与“正常”光照条件时期相比，在24小时黑暗时期上夜班的工人的皮质醇水平没有差异，但在24小时黑暗时期上白班的工人的皮质醇节律紊乱（醒来后峰值较低且白天缺乏正常下降）。
外部光照条件和轮班安排是调节工人皮质醇节律的重要因素。在孤立且极端的环境中，似乎适应夜间节律比适应清晨节律更容易。
