title: The relationship between 63days of 24-h urinary free cortisol and hair cortisol levels in 10 healthy individuals.
abstract: Interest in measuring cortisol in scalp hair is increasing because of its assumed ability to provide a historical timeline of previous systemic levels of cortisol. Yet, it remains uncertain how well hair cortisol represents the total systemic secretion of cortisol over time.
  
  
  
  Ten healthy individuals collected 24-h urine samples for 63 consecutive days and provided a hair sample at the end of the study period. 24-h urinary creatinine levels in every urine sample were determined to assess completeness of the samples. Cortisol levels in 24-h urine samples and in hair were measured with liquid chromatography tandem mass spectrometry. The correlations between urinary cortisol and hair cortisol were calculated using Kendall's tau.
  
  
  
  We found a nonsignificant moderate correlation between average urinary cortisol secretion and average hair cortisol concentration rт=0.422, p=0.089.
  
  
  
  Hair cortisol concentration correlates low to moderately with 24-h urinary cortisol concentration over a period of 63days.
authors: University of Groningen, University Medical Center Groningen, Interdisciplinary Center Psychopathology and Emotion regulation (ICPE), Department of Psychiatry, The Netherlands. Electronic address: sonjaleonie@yahoo.com.
authors: S L
authors: SL
authors: van Ockenburg
authors: University of Groningen, University Medical Center Groningen, Interdisciplinary Center Psychopathology and Emotion regulation (ICPE), Department of Psychiatry, The Netherlands.
authors: H M
authors: HM
authors: Schenk
authors: University of Groningen, University Medical Center Groningen, Department of Laboratory Medicine, Groningen, The Netherlands.
authors: A
authors: A
authors: van der Veen
authors: Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands.
authors: E F C
authors: EF
authors: van Rossum
authors: University of Groningen, University Medical Center Groningen, Department of Laboratory Medicine, Groningen, The Netherlands.
authors: I P
authors: IP
authors: Kema
authors: University of Groningen, University Medical Center Groningen, Interdisciplinary Center Psychopathology and Emotion regulation (ICPE), Department of Psychiatry, The Netherlands.
authors: J G M
authors: JG
authors: Rosmalen
mesh_terms: D000328:Adult; D005260:Female; D006197:Hair / Q000737:chemistry*; D064368:Healthy Volunteers; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism* / Q000652:urine; D008297:Male; D008875:Middle Aged; D053719:Tandem Mass Spectrometry; D013997:Time Factors; D055815:Young Adult
chemical_list: D006854:Hydrocortisone
keywords: Cortisol; Hair; Hair cortisol; Humans; Hypothalamic-pituitary-adrenal axis; Urine