title: Frequent cellular phone use modifies hypothalamic-pituitary-adrenal axis response to a cellular phone call after mental stress in healthy children and adolescents: A pilot study.
abstract: OBJECTIVE
  The hypothalamic-pituitary-adrenal (HPA) axis is the main "gate-keeper" of the organism's response to every somatic or mental stress. This prospective study aims to investigate the HPA-axis response to a cellular phone call exposure after mental stress in healthy children and adolescents and to assess the possible predictive role of baseline endocrine markers to this response.
  
  
  METHODS
  Two groups of healthy school-age children aged 11-14 (12.5±1.5) years were included in the study, the one comprising those who are occasional users of a cellular phone (Group A) while the second those who do regularly use one (Group B). Blood samples were obtained from all participants at 8.00 am after a 12-hour overnight fasting for thyroid hormone, glucose, insulin, and cortisol levels determination. The participants performed the Trier Social Stress Test for Children (TSST-C) (5 minoral task followed by 5 min arithmetic task). Salivary cortisol samples were obtained at baseline, 10' and 20' min after the TSST-C and 10' and 20' after a 5 minute cellular phone call.
  
  
  RESULTS
  Significant changes in the salivary cortisol levels were noted between 10' and 20' mins after the cellular phone call with different responses between the two groups. Baseline thyroid hormone levels seem to predict the cortisol response to mental stress mainly in group A, while HOMA had no impact on salivary cortisol response at any phase of the test, in either group.
  
  
  CONCLUSIONS
  HPA axis response to cellular phone after mental stress in children and adolescents follow a different pattern in frequent users than in occasional users that seems to be influenced by the baseline thyroid hormone levels.
authors.affiliation: First Department of Paediatrics, University of Athens Medical School, "Aghia Sophia" Children's Hospital, Athens, Greece; Clinical, Experimental Surgery and Translational Research Centre, Biomedical Research Foundation Academy of Athens, Athens, Greece. Electronic address: sgeronik@gmail.com.
authors.forename: Styliani A
authors.initials: SA
authors.lastname: Geronikolou
authors.affiliation: Clinical, Experimental Surgery and Translational Research Centre, Biomedical Research Foundation Academy of Athens, Athens, Greece.
authors.forename: Aikaterini
authors.initials: A
authors.lastname: Chamakou
authors.affiliation: Department of Endocrinology, Eugenideion Hospital, University of Athens, Athens, Greece.
authors.forename: Aimilia
authors.initials: A
authors.lastname: Mantzou
authors.affiliation: First Department of Paediatrics, University of Athens Medical School, "Aghia Sophia" Children's Hospital, Athens, Greece; Clinical, Experimental Surgery and Translational Research Centre, Biomedical Research Foundation Academy of Athens, Athens, Greece; Department of Endocrinology, Eugenideion Hospital, University of Athens, Athens, Greece.
authors.forename: George
authors.initials: G
authors.lastname: Chrousos
authors.affiliation: First Department of Paediatrics, University of Athens Medical School, "Aghia Sophia" Children's Hospital, Athens, Greece.
authors.forename: Christina
authors.initials: C
authors.lastname: KanakaGantenbein
mesh_terms: D000293:Adolescent; D040421:Cell Phone / Q000706:statistics & numerical data*; D002648:Child; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism; D007328:Insulin / Q000378:metabolism; D008297:Male; D010913:Pituitary-Adrenal System / Q000378:metabolism*; D013315:Stress, Psychological / Q000378:metabolism*
chemical_list: D007328:Insulin; D006854:Hydrocortisone
keywords: Adolescents; Cellular phone exposure; HPA axis; Salivary cortisol; Thyroid hormones; Trier Social Stress Test