FP11-4 Assessment of Normal Salivary Cortisol Values in Children Using Mass Spectrometry

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: FP11-Pediatric Endocrinology
Saturday, June 15, 2013: 11:00 AM-11:30 AM
Presentation Start Time: 11:15 AM
Room 104 (Moscone Center)

Poster Board SAT-597
Rajiv B. Kumar*1, Run Zhang Shi2, Nicole K. Schleifer1 and Tandy Aye1
1Stanford University Medical Center, Stanford, CA, 2Stanford University, Palo Alto, CA
Background:  Current methods to measure cortisol levels, either by venipuncture or 24 hour urine collection, are impractical for the pediatric population. Salivary cortisol measurement using an antibody based assay is available; however there is cross-reactivity, and limited pediatric normative data.  We report preliminary data from an ongoing study using mass spectrometry to measure salivary cortisol in healthy children.                                                                                                    

Design:  Children age 3-17y without chronic medical illness including pituitary or adrenal pathologies and/or recent use of systemic glucocorticoids participated in the study.  After viewing detailed instructions on salivary sample collection, the subjects/caregivers collected samples on two different dates at their usual bedtime, midnight, and upon waking the following morning. 

Results: 183 viable samples have been submitted from 37 children to date: 18 subjects were <8y, 10 were 8-12y, and 9 were 13-17y.  Salivary cortisol values (ng/dL) are reported as mean ± SD (range): Bedtime All = 45.3 ± 81.7 (<20-557), <8y = 66.1 ± 117.0 (<20-557), ≥8y = 28.6 ± 25.3 (<20-135); Midnight All = 44.5 ± 84.9 (<20-583), <8y = 73.9 ± 140.3 (<20-583), ≥8y = 30.2 ± 30.3 (<20-135); Morning All = 244.7 ± 261.9 (<20-1790), <8y = 274.0 ± 323.7 (<20-1790), ≥8y = 219.1 ± 193.7 (<20-1100).  Caregivers for children <8y noted difficulty in sample collection including emotional distress.  For this group, we noted wide cortisol variability and frequently insufficient quantity of saliva (especially at midnight).  The bedtime and midnight cortisol levels for all groups were comparable (p-values >0.80).  The morning levels were significantly higher than the bedtime and midnight values (p-values <0.01).  

Conclusion:  These results suggest that adult norms may not apply to the pediatric population.  Additionally, bedtime is comparable to midnight measurement, and morning measurement does demonstrate diurnal variation in cortisol secretion. Salivary cortisol measurement by mass spectrometry may be an attractive alternative to the current techniques, though this testing may not be optimal for children <8y.

Nothing to Disclose: RBK, RZS, NKS, TA

*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm