OBJECTIVES: The study examines the components of biological variation of nocturnal salivary cortisol in healthy subjects. DESIGN AND METHODS: Eight repetitive measurements were performed in seven subjects during a 25-day time period (study A), and then, for comparison, two salivary specimens were taken during two consecutive days from 20 subjects (study B). Salivary cortisol was measured with the Salimetrics HS-Cortisol assay. RESULTS: Mean salivary cortisol (1.27 nmol/L), analytical variation (CVa=15.4%), within-subject variation (CVi=34.1%), between-subject variation (CVg=35.3%), index of individuality (II=1.06) and reference change value (RCV=104%) were obtained for study A. Similar results were obtained from the set of samples of study B. CONCLUSION: The study results show a medium degree of individuality for salivary cortisol. Both conventional reference values and comparison of serial results may be equally used for clinical interpretation. A change greater of 104% between two successive measurements should be considered significant.
OBJECTIVES: The study examines the components of biological variation of nocturnal salivary cortisol in healthy subjects. DESIGN AND METHODS: Eight repetitive measurements were performed in seven subjects during a 25-day time period (study A), and then, for comparison, two salivary specimens were taken during two consecutive days from 20 subjects (study B). Salivary cortisol was measured with the Salimetrics HS-Cortisol assay. RESULTS: Mean salivary cortisol (1.27 nmol/L), analytical variation (CVa=15.4%), within-subject variation (CVi=34.1%), between-subject variation (CVg=35.3%), index of individuality (II=1.06) and reference change value (RCV=104%) were obtained for study A. Similar results were obtained from the set of samples of study B. CONCLUSION: The study results show a medium degree of individuality for salivary cortisol. Both conventional reference values and comparison of serial results may be equally used for clinical interpretation. A change greater of 104% between two successive measurements should be considered significant.
Authors: John Newell-Price; Rosario Pivonello; Antoine Tabarin; Maria Fleseriu; Przemysław Witek; Mônica R Gadelha; Stephan Petersenn; Libuse Tauchmanova; Shoba Ravichandran; Pritam Gupta; André Lacroix; Beverly M K Biller Journal: Eur J Endocrinol Date: 2020-02 Impact factor: 6.664
Authors: James W Findling; Maria Fleseriu; John Newell-Price; Stephan Petersenn; Rosario Pivonello; Albert Kandra; Alberto M Pedroncelli; Beverly M K Biller Journal: Endocrine Date: 2016-05-21 Impact factor: 3.633