Effect of Collection Methods on Salivary Cortisol

Christopher JD McKinlay^1,3,4, Eric B Thorstensen¹, Wayne S Cutfield^1,5, Malcolm R Battin^1,2, Stuart R Dalziel^1,6 and Jane E Harding^1*

¹Liggins Institute, University of Auckland, Auckland, New Zealand

²Newborn Services, National Women’s Health, Auckland City Hospital, Auckland, New Zealand

³Department of Paediatrics: Child and Youth Health, University of Auckland, Auckland New Zealand

⁴Kidz First Neonatal Care, Counties Manukau Health, Auckland, New Zealand

⁵A Better Start, National Science Challenge, New Zealand

⁶Children’s Emergency Department, Starship Children’s Health, Auckland, New Zealand

*Corresponding Author : Jane E Harding
Liggins Institute, The University of Auckland, Private Bag 92019, Victoria St West, Auckland 1142, New Zealand
Tel: +64 (9) 373 7599
Fax: 82733; +64 (21) 515979
E-mail: j.harding@auckland.ac.nz

Received: August 14, 2017 Accepted: October 17, 2017 Published: October 22, 2017

Citation: McKinlay CJD, Thorstensen EB, Cutfield WS, Battin MR, Dalziel SR, et al. (2017) Effect of Collection Methods on Salivary Cortisol. J Diagn Tech Biomed Anal 6:2. doi: 10.4172/2469-5653.1000121

Salivary cortisol is a useful measure of hypothalmic-pituitary axis function, but the effects of collection method, sample volume, and environmental conditions on hormone recovery are poorly described. These potential sources of pre-analytical variation were assessed using spiked pooled saliva and assay by liquid chromatography and tandem mass spectrometry (LC-MS/MS). When saliva was collected onto cotton swabs, hormone recovery was determined primarily by volume recovery, which was in turn determined by sample volume. To ensure adequate cortisol recovery, ≥2 ml of saliva must be absorbed onto swabs. This may be difficult for many children and some adults to achieve. Salivary cortisol is remarkably stable to a range of environmental conditions, including repeated freeze-thaw cycles, storage at room temperature and exposure to sunlight. This study shows that it is preferable to obtain saliva by passive drool without swabs if adequate sample volume (≥2 ml) cannot be achieved, and that saliva samples can be returned by standard post without affecting hormone recovery.