title: Elevated resting heart rate as a predictor of posttraumatic stress disorder after severe traumatic brain injury.
abstract: OBJECTIVE
  This study indexed the relationship between resting heart rates (HRs) after injury and subsequent posttraumatic stress disorder (PTSD) in patients who sustained severe traumatic brain injury (TBI).
  
  
  METHODS
  Patients who sustained a severe TBI (N = 68) had their resting HR assessed 1 week and 1 month after injury, and they were assessed for PTSD 6 months after injury with the PTSD Interview, a structured clinical interview based on the criteria of the Diagnostic and Statistical Manual of Mental Disorders, 3rd Edition, Revised.
  
  
  RESULTS
  PTSD was diagnosed in 23% of patients. PTSD participants had higher HRs at 1 week but not at 1 month after trauma than non-PTSD participants. This difference remained significant when the effect of posttraumatic amnesia was controlled, but it was not significant when the effect of Glasgow Coma Scale was controlled.
  
  
  CONCLUSIONS
  These findings accord with the proposal that fear conditioning can occur outside the level of awareness and contribute to PTSD development.
authors.affiliation: School of Psychology, University of New South Wales, New South Wales, 2052, Australia. r.bryant@unsw.edu.au
authors.forename: Richard A
authors.initials: RA
authors.lastname: Bryant
authors.forename: Jeno E
authors.initials: JE
authors.lastname: Marosszeky
authors.forename: Jenelle
authors.initials: J
authors.lastname: Crooks
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Gurka
mesh_terms: D000328:Adult; D000647:Amnesia / Q000175:diagnosis / Q000209:etiology; D001930:Brain Injuries / Q000150:complications* / Q000175:diagnosis; D005260:Female; D005500:Follow-Up Studies; D015600:Glasgow Coma Scale; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D011569:Psychiatric Status Rating Scales; D012307:Risk Factors; D013313:Stress Disorders, Post-Traumatic / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology