title: Altered circadian patterns of salivary cortisol in low-functioning children and adolescents with autism.
abstract: BACKGROUND
  Reports of higher stress responsivity, altered sleep-wake cycle and a melatonin deficit in autism have stimulated interest in the cortisol circadian rhythm in individuals with autism.
  
  
  METHODS
  The study was conducted on 55 low-functioning children and adolescents with autism (11.3 ± 4.1 years-old) and 32 typically developing controls (11.7 ± 4.9 years-old) matched for age, sex and puberty. Behavioral assessment was performed using the Autism Diagnostic Observation Schedule (ADOS). Salivary samples for measurement of cortisol were collected during a 24-h period (at least 0800 h-Day 1, 1600 h, 0800 h-Day 2 for 46 individuals with autism and 27 controls, and 0800 h-Day 1, 1100 h, 1600 h, 2400 h, 0800 h-Day 2 for 13 individuals with autism and 20 controls). Overnight (2000 h-0800 h) urinary cortisol excretion was also measured.
  
  
  RESULTS
  The autism group displayed significantly higher levels of salivary cortisol at all time-points, flatter daytime and nighttime slopes, higher 0800 h cortisol levels on Day 2 compared to Day 1, and greater variances of salivary and urinary cortisol. There was a significant relationship between salivary cortisol levels and impairments in social interaction and verbal language. Overnight urinary cortisol excretion was similar in the autism and control groups.
  
  
  CONCLUSIONS
  Anticipation of the stressful collection procedure appears to contribute to the higher 0800 h-Day 2 versus 0800 h-Day 1 salivary cortisol levels in autism. This sensitization to stressors might be as, or even more, important clinically than exposure to novelty in autism. The similar group means for overnight urinary cortisol excretion indicate that basal HPA axis functioning is unaltered in low-functioning autism. The elevated salivary cortisol levels observed in autism over the 24-h period in a repeated stressful condition, flattened diurnal cortisol patterns and the apparent effect of anticipation are consistent with prior findings in high trait anxiety.
authors.affiliation: Pôle Hospitalo-Universitaire de Psychiatrie de l'Enfant et de l'Adolescent de Rennes (PHUPEA), CHGR et Université de Rennes 1, Rennes, France; Laboratoire Psychologie de la Perception, Université Paris Descartes, CNRS UMR 8158, Paris, France. Electronic address: s.tordjman@yahoo.fr.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Tordjman
authors.affiliation: Child Study Center, Yale University School of Medicine, New-Haven, CT, USA.
authors.forename: George M
authors.initials: GM
authors.lastname: Anderson
authors.affiliation: Pôle Hospitalo-Universitaire de Psychiatrie de l'Enfant et de l'Adolescent de Rennes (PHUPEA), CHGR et Université de Rennes 1, Rennes, France; Laboratoire Psychologie de la Perception, Université Paris Descartes, CNRS UMR 8158, Paris, France.
authors.forename: Solenn
authors.initials: S
authors.lastname: Kermarrec
authors.affiliation: Service Universitaire de Psychiatrie de l'Enfant et de l'Adolescent, CHU de Nantes, Nantes, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Bonnot
authors.affiliation: Service Universitaire de Psychiatrie de l'Enfant et de l'Adolescent, Hôpital le Vinatier, Bron, France.
authors.forename: Marie-Maude
authors.initials: MM
authors.lastname: Geoffray
authors.affiliation: INSERM U 693, Université Paris-Sud, Faculté de Médecine Paris-Sud, Le Kremlin-Bicêtre, France; AP-HP, CHU Bicêtre, Service de Génétique Moléculaire, Pharmacogénétique et Hormonologie, Le Kremlin-Bicêtre, France.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Brailly-Tabard
authors.affiliation: AP-HP, CHU Bicêtre, Service de Génétique Moléculaire, Pharmacogénétique et Hormonologie, Le Kremlin-Bicêtre, France.
authors.forename: Amel
authors.initials: A
authors.lastname: Chaouch
authors.affiliation: AP-HP, CHU Bicêtre, Service de Génétique Moléculaire, Pharmacogénétique et Hormonologie, Le Kremlin-Bicêtre, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Colliot
authors.affiliation: INSERM U 693, Université Paris-Sud, Faculté de Médecine Paris-Sud, Le Kremlin-Bicêtre, France; AP-HP, CHU Bicêtre, Service de Génétique Moléculaire, Pharmacogénétique et Hormonologie, Le Kremlin-Bicêtre, France.
authors.forename: Severine
authors.initials: S
authors.lastname: Trabado
authors.affiliation: Maison Départementale de l'Adolescent et Centre Médico-Psycho-Pédagogique, Conseil Général des Bouches-du-Rhône, France; Laboratoire de Santé Publique EA3279, Faculté de Médecine de Marseille, France.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Bronsard
authors.affiliation: Laboratoire Psychologie de la Perception, Université Paris Descartes, CNRS UMR 8158, Paris, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Coulon
authors.affiliation: Service Hospitalo-Universitaire de Psychiatrie de l'Enfant et de l'Adolescent de Brest, EA4686, UBO, Brest, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Botbol
authors.affiliation: Medical Biochemistry and Molecular Biology, Paris 6 School of Medicine, Paris, France.
authors.forename: Henriette
authors.initials: H
authors.lastname: Charbuy
authors.affiliation: Chronobiology Unit, Rothschild Foundation, Paris, France.
authors.forename: Françoise
authors.initials: F
authors.lastname: Camus
authors.affiliation: Chronobiology Unit, Rothschild Foundation, Paris, France.
authors.forename: Yvan
authors.initials: Y
authors.lastname: Touitou
mesh_terms: D000293:Adolescent; D001321:Autistic Disorder / Q000503:physiopathology*; D002648:Child; D002940:Circadian Rhythm / Q000502:physiology*; D003071:Cognition / Q000502:physiology; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000032:analysis*; D007030:Hypothalamo-Hypophyseal System / Q000503:physiopathology*; D008297:Male; D009483:Neuropsychological Tests; D010913:Pituitary-Adrenal System / Q000503:physiopathology*; D012463:Saliva / Q000737:chemistry; D013315:Stress, Psychological / Q000503:physiopathology
chemical_list: D006854:Hydrocortisone
keywords: Autism; Basal cortisol levels; Circadian rhythm; Cortisol; Flattened cortisol patterns; Repeated stress; Sensitization to stressors; Stress response; Trait anxiety