title: Tonic and phasic heart rate as predictors of posttraumatic stress disorder.
abstract: OBJECTIVE
  To examine the relationship between acute measures of a) heart rate (HR) immediately after traumatic injury, b) tonic (resting) HR at 1 week post injury, c) phasic (aroused) HR at 1 week post injury, and d) somatic symptoms of arousal in the prediction of subsequent posttraumatic stress disorder (PTSD). Fear conditioning models propose that HR reactivity shortly after trauma may predict PTSD.
  
  
  METHODS
  In a longitudinal study, consecutive injury survivors (n = 197) admitted to a hospital trauma service were assessed within 1 week and at 12 months post injury. HR was assessed by paramedics at the site of the trauma and pulse oximetry technology at 1 week post trauma. Somatic symptoms of arousal were measured using the somatic scale on the Beck Anxiety Inventory (BAI). PTSD was assessed using the Clinician Administered PTSD Scale at 12 months.
  
  
  RESULTS
  At 12 months post injury, PTSD was diagnosed in 10% of participants. Only HR change scores (phasic - tonic HR) and BAI scores significantly predicted later PTSD.
  
  
  CONCLUSIONS
  These findings question the clinical usefulness of tonic HR as a biological marker of later PTSD. The finding that HR reactivity (phasic - tonic) predicts later PTSD has theoretical importance. The strongest predictor of later PTSD was somatic arousal.
authors.affiliation: Australian Centre for Posttraumatic Mental Health, P.O. Box 5444, West Heidelberg, Victoria 3091, Australia. mod@unimelb.edu.au
authors.forename: Meaghan L
authors.initials: ML
authors.lastname: O'Donnell
authors.forename: Mark
authors.initials: M
authors.lastname: Creamer
authors.forename: Peter
authors.initials: P
authors.lastname: Elliott
authors.forename: Richard
authors.initials: R
authors.lastname: Bryant
mesh_terms: D000328:Adult; D000368:Aged; D001007:Anxiety / Q000453:epidemiology / Q000209:etiology; D001143:Arousal; D001930:Brain Injuries / Q000503:physiopathology; D003214:Conditioning, Classical; D003463:Cues; D004632:Emergency Medical Services; D005239:Fear; D005260:Female; D005500:Follow-Up Studies; D006339:Heart Rate; D006801:Humans; D008297:Male; D008487:Medical History Taking; D008875:Middle Aged; D008960:Models, Psychological; D010092:Oximetry; D010173:Palpation; D011237:Predictive Value of Tests; D013313:Stress Disorders, Post-Traumatic / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D013564:Sympathetic Nervous System / Q000503:physiopathology; D015599:Trauma Severity Indices; D014947:Wounds and Injuries / Q000150:complications / Q000503:physiopathology / Q000523:psychology