title: Physiological Markers of Arousal Change with Psychological Treatment for Insomnia: A Preliminary Investigation.
abstract: OBJECTIVE
  The aim of this preliminary study was to evaluate if Sleep Restriction Therapy for insomnia is associated with modifications to physiological arousal, indexed through overnight measures of plasma cortisol concentrations and core body temperature.
  
  
  METHODS
  In a pre-to-post open label study design, eleven patients with chronic and severe Psychophysiological Insomnia underwent 5 weeks of Sleep Restriction Therapy.
  
  
  RESULTS
  Eight (73%) patients out of 11 consented completed therapy and showed a decrease in insomnia severity pre-to-post treatment (mean (SD): 18.1 (2.8) versus 8.4 (4.8); p = .001). Six patients were analyzed with pre-to-post overnight measures of temperature and cortisol. Contrary to our hypothesis, significantly higher levels of plasma cortisol concentrations were found during the early morning at post-treatment compared to baseline (p < .01), while no change was observed in the pre-sleep phase or early part of the night. Core body temperature during sleep was however reduced significantly (overall mean [95% CI]: 36.54 (°C) [36.3, 36.8] versus 36.45 [36.2, 36.7]; p < .05).
  
  
  CONCLUSIONS
  Sleep Restriction Therapy therefore was associated with increased early morning cortisol concentrations and decreased core body temperature, supporting the premise of physiological changes in functioning after effective therapy. Future work should evaluate change in physiological variables associated with clinical treatment response.
  
  
  BACKGROUND
  Australian New Zealand Clinical Trials Registry ANZCTR 12612000049875.
authors.affiliation: Centre for Integrated Research and Understanding of Sleep (CIRUS), NeuroSleep and Woolcock Institute of Medical Research, University of Sydney, Sydney, Australia.
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Miller
authors.affiliation: Sleep & Circadian Neuroscience Institute, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom.
authors.forename: Simon D
authors.initials: SD
authors.lastname: Kyle
authors.affiliation: Centre for Integrated Research and Understanding of Sleep (CIRUS), NeuroSleep and Woolcock Institute of Medical Research, University of Sydney, Sydney, Australia.|Sydney Nursing School, University of Sydney, Sydney, Australia.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Gordon
authors.affiliation: Sleep & Circadian Neuroscience Institute, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom.
authors.forename: Colin A
authors.initials: CA
authors.lastname: Espie
authors.affiliation: Centre for Integrated Research and Understanding of Sleep (CIRUS), NeuroSleep and Woolcock Institute of Medical Research, University of Sydney, Sydney, Australia.|Department of Respiratory and Sleep Medicine, RPAH, Sydney Local Health District, Sydney, Australia.
authors.forename: Ronald R
authors.initials: RR
authors.lastname: Grunstein
authors.affiliation: Centre for Integrated Research and Understanding of Sleep (CIRUS), NeuroSleep and Woolcock Institute of Medical Research, University of Sydney, Sydney, Australia.
authors.forename: Anna E
authors.initials: AE
authors.lastname: Mullins
authors.affiliation: School of Physics, University of Sydney, Sydney, Australia.
authors.forename: Svetlana
authors.initials: S
authors.lastname: Postnova
authors.affiliation: Centre for Integrated Research and Understanding of Sleep (CIRUS), NeuroSleep and Woolcock Institute of Medical Research, University of Sydney, Sydney, Australia.
authors.forename: Delwyn J
authors.initials: DJ
authors.lastname: Bartlett
mesh_terms: D000328:Adult; D001143:Arousal; D015415:Biomarkers / Q000097:blood; D001831:Body Temperature; D002940:Circadian Rhythm; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D008297:Male; D008875:Middle Aged; D012890:Sleep; D007319:Sleep Initiation and Maintenance Disorders / Q000097:blood / Q000628:therapy*; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D006854:Hydrocortisone