Salivary cortisol and alpha-amylase: Is there consistency between psychosocial stress test and burdensome work shifts?

ABSTRACT

This study examined the consistency of salivary cortisol and alpha-amylase (sAA) total daily secretion between laboratory and field circumstances. The 95 participants were shift working female health care professionals with high (n = 53) or low (n = 42) psychosocial stress (job strain) measured by the Job Content Questionnaire (JCQ). The Trier Social Stress Test including a 5-min free speech and a mental arithmetic task was conducted with four, and field measurements with three daily saliva samples of cortisol and sAA during circadian rhythm and inter-shift recovery controlled morning shift, night shift, and a day off. The associations of salivary cortisol and sAA area under the curve with respect to ground (AUCg) and area under the curve with respect to increase (AUCi) between laboratory and field were tested using OLS (Ordinary Least Squares) regression. The sAA AUCg output in the laboratory was correlated with the output during all field measurement days and similarly among high and low job strain groups (p < 0.001). SAA AUCi and salivary cortisol AUCg and AUCi were not correlated between laboratory and field measurement, neither in the whole sample nor among the low or high job strain group. In conclusion, a laboratory measure of sAA AUCg output is promising in predicting stress-related output during burdensome work shifts and leisure time, whereas sAA AUCi or salivary cortisol seem not to have this potential.

KEYWORDS:

• Biomarker
• night shift work
• Trier Social Stress Test
• work-related stress

Acknowledgments

We thank Elise Koskenseppä for the participant recruitment, Nina Lapveteläinen and Riitta Velin for making the arrangements for the field measurements, Sirpa Hyttinen for the analysis of saliva samples, Jaana Pentti, Hanna Kaisa Hyvärinen, and Ritva Luukkonen for statistical support.

Funding

This study was supported by the Academy of Finland (projects 124473 and 132944), the Finnish Work Environment Fund (project 107156 and grant 113334), the SalWe Research Program (TEKES -the Finnish Funding Agency for Technology and Innovation, grant 1104/10), and the EU New OSH ERA Research Programme.

NordForsk, Nordic Program on Health and Welfare (74809) has provided support for Mikko Härmä, Kati Karhula, Sampsa Puttonen and Mikael Sallinen. Marko Elovainio was supported by the Academy of Finland (265977). Mika Kivimäki is supported by a professorial fellowship from the Economic and Social Research Council, UK and NordForsk, the Nordic Programme on Health and Welfare (75021).