Search Results
Search for other papers by Marcus Imamovic in
Google Scholar
PubMed
Search for other papers by Nils Bäcklund in
Google Scholar
PubMed
Search for other papers by Staffan Lundstedt in
Google Scholar
PubMed
Search for other papers by Göran Brattsand in
Google Scholar
PubMed
Search for other papers by Elisabeth Aardal in
Google Scholar
PubMed
Search for other papers by Tommy Olsson in
Google Scholar
PubMed
Search for other papers by Per Dahlqvist in
Google Scholar
PubMed
Objective
To determine the effects of liquorice consumption, topical hydrocortisone, and blood contamination on salivary cortisol and cortisone concentrations.
Design and methods
Thirty healthy volunteers were randomized to a low, medium, or high dose of liquorice. Late-night saliva samples were collected using a Salivette® collection device at baseline, during 1 week of daily liquorice consumption, and during 4 weeks' washout. Saliva sampling was also performed before and after the application of topical hydrocortisone on the skin. Furthermore, in a subgroup (n = 16), saliva and venous blood were collected from each individual and mixed to achieve graded blood contamination in saliva. Salivary cortisol and cortisone were analyzed with liquid chromatography-tandem mass spectrometry.
Results
Significant increases in salivary cortisol concentrations were observed during medium- (+49%) and high-dose (+97%) liquorice intake, which returned to baseline 4 days after liquorice withdrawal. Topical hydrocortisone on fingers holding the collection swab increased salivary cortisol concentrations >1000-fold with concomitant pronounced elevation of the cortisol:cortisone ratio. Salivary cortisol increased significantly after contamination with blood ≥0.5%. Visual examination could safely detect these samples. Salivary cortisone concentrations were unaffected by liquorice consumption and blood contamination, and only marginally affected by topical hydrocortisone.
Conclusion
Liquorice, topical hydrocortisone, and blood contamination may all cause elevated salivary cortisol concentrations. Improved sampling instructions and visual examination of the sample may minimize these risks. Salivary cortisone is essentially unaffected by the different preanalytical confounders and may be used as a first-line screening test for Cushing's syndrome.