Day-to-day differences in cortisol levels and molar cortisol-to-DHEA ratios among working individuals.
OBJECTIVE
The present study was carried out to determine day-to-day differences in cortisol levels and the molar cortisol-to-dehydroepiandrosterone (DHEA) ratio (molar C/D ratio) in working subjects.


METHODS
The cortisol and DHEA levels were measured from saliva samples collected 30 minutes after awakening for 7 consecutive days in full-time working subjects that worked Monday through Saturday. To determine the day-to-day differences within subjects, the collected data was analyzed using variance (ANOVA) for a randomized complete block design (RCBD).


RESULTS
The cortisol levels from samples collected 30 minutes after awakening on workdays were similar to each other, but were significantly different from the cortisol levels on Sunday. The DHEA levels were not significantly different between the days of week. The DHEA levels on Monday and Tuesday were relatively lower than the levels on the other weekdays. The DHEA levels on Thursday and Friday were relatively higher than the other days. The molar C/D ratios on Sunday were significantly lower than those on workdays. The molar C/D ratios on Monday and Tuesday were significantly higher than those on Wednesday or other workdays.


CONCLUSIONS
The cortisol levels and the molar C/D ratios demonstrate differences in adrenocortical activities between workdays and non-workdays, but the molar C/D ratio additionally represents differences in adrenocortical status between the first two workdays and other workdays. Thus, it is possible that the day-to-day differences in the cortisol levels and the molar C/D ratio represent the adrenal response to upcoming work-related stress.
Kim
Min-Soo
MS
Department of Statistics, Chonnam National University, Gwangju, Korea.
Lee
Young-Jin
YJ
Ahn
Ryun-Sup
RS
D000328:Adult; D000704:Analysis of Variance; D003687:Dehydroepiandrosterone / Q000378:metabolism*; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D012463:Saliva / Q000737:chemistry; D014937:Work / Q000502:physiology*
D003687:Dehydroepiandrosterone; D006854:Hydrocortisone