Higher saliva stress hormone levels after sleep loss in a night shift worker

One subject exhibited a 6-fold increase in salivary cortisol levels during the morning shift compared to normal values during evening and night shifts.

• Salivary cortisol levels were measured in 63 shift-workers during different shifts.
• The individual mean cortisol level for the subject was 48.4 nmol/l, while the group mean was 8.9 nmol/l.
• Peak cortisol levels for the subject reached 67.8 nmol/l, compared to a group peak of 11.0 nmol/l.
• Retrospective questioning indicated the subject had no signs of long-term stress.
• The cortisol increase may be associated with sleep deprivation from rapidly rotating shifts.

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