title: Hair cortisol as a novel biomarker of HPA suppression by inhaled corticosteroids in children.
abstract: BACKGROUND
  Asthma is the most common chronic condition in childhood, and the recommended pharmacotherapy for long-term control includes the use of inhaled corticosteroids (ICS). ICS were designed to act at the site of inflammation in the lung, thus decreasing systemic absorption and reducing the risk of adverse effects associated with corticosteroid use (e.g., HPA suppression and its consequent effects). Available data show that measurement of hair cortisol successfully reflects endogenous cortisol levels. We sought to examine whether hair cortisol measurements can be used to identify HPA suppression surrounding ICS therapy in children with asthma.
  
  
  METHODS
  Hair samples were collected from the vertex posterior region of the head of 18 asthmatic children. We compared their hair cortisol concentration during ICS use with the concentration prior to ICS use.
  
  
  RESULTS
  During ICS therapy, median hair cortisol levels were twofold lower compared with the period of no ICS use (median 89.8 ng/g vs. 198.2 ng/g, P = 0.0015).
  
  
  CONCLUSIONS
  Hair cortisol is an effective biomarker of the HPA suppression associated with ICS therapy and can be a sensitive tool for determining systemic effects of ICS use and monitoring adherence. Future research is needed to characterize the effect of untreated asthma on hair cortisol concentrations, if any.
authors: 1] The Motherisk Program, Division of Clinical Pharmacology and Toxicology, The Hospital for Sick Children, Toronto, Ontario, Canada [2] Graduate Department of Pharmaceutical Science, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada.
authors: Laura
authors: L
authors: Smy
authors: 1] Child & Family Research Institute, Vancouver, British Columbia, Canada [2] Division of Translational Therapeutics, Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada [3] Pharmaceutical Outcomes Programme, BC Children's Hospital, Vancouver, British Columbia, Canada.
authors: Kaitlyn
authors: K
authors: Shaw
authors: 1] Child & Family Research Institute, Vancouver, British Columbia, Canada [2] Division of Translational Therapeutics, Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada [3] Pharmaceutical Outcomes Programme, BC Children's Hospital, Vancouver, British Columbia, Canada.
authors: Anne
authors: A
authors: Smith
authors: Department of Physiology and Pharmacology, Western University, London, Ontario, Canada.
authors: Evan
authors: E
authors: Russell
authors: Department of Physiology and Pharmacology, Western University, London, Ontario, Canada.
authors: Stan
authors: S
authors: Van Uum
authors: Department of Physiology and Pharmacology, Western University, London, Ontario, Canada.
authors: Michael
authors: M
authors: Rieder
authors: 1] Child & Family Research Institute, Vancouver, British Columbia, Canada [2] Division of Translational Therapeutics, Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada [3] Pharmaceutical Outcomes Programme, BC Children's Hospital, Vancouver, British Columbia, Canada.
authors: Bruce
authors: B
authors: Carleton
authors: 1] The Motherisk Program, Division of Clinical Pharmacology and Toxicology, The Hospital for Sick Children, Toronto, Ontario, Canada [2] Graduate Department of Pharmaceutical Science, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada [3] Department of Physiology and Pharmacology, Western University, London, Ontario, Canada.
authors: Gideon
authors: G
authors: Koren
mesh_terms: D000280:Administration, Inhalation; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage* / Q000009:adverse effects*; D018927:Anti-Asthmatic Agents / Q000008:administration & dosage / Q000009:adverse effects; D001249:Asthma / Q000150:complications / Q000188:drug therapy; D015415:Biomarkers / Q000737:chemistry*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006197:Hair / Q000737:chemistry*; D006801:Humans; D006854:Hydrocortisone / Q000737:chemistry*; D007030:Hypothalamo-Hypophyseal System / Q000187:drug effects*; D007223:Infant; D007249:Inflammation; D008297:Male
chemical_list: D000305:Adrenal Cortex Hormones; D018927:Anti-Asthmatic Agents; D015415:Biomarkers; D006854:Hydrocortisone