Examining the Prospective Relationship between Pre-Disaster Respiratory Sinus Arrhythmia and Post-Disaster Posttraumatic Stress Disorder Symptoms in Children.

Previous studies have examined the concurrent relationship between posttraumatic stress disorder (PTSD) and a range of psychophysiological variables, including respiratory sinus arrhythmia (RSA). However, there is a lack of research examining the prospective development of trauma symptomatology, and the directionality of the association between RSA level and PTSD has yet to be determined. The current study is the first prospective study to examine whether RSA level and RSA reactivity are risk factors for PTSD symptoms in children. Assessments were conducted both prior to (Time 1) and following (Time 2) a natural disaster (i.e., Hurricane Katrina). Participants were 36 children who were 3-6 years-old during the Time 1 assessment. Structured diagnostic interviews were used to assess PTSD symptoms at both Time 1 and Time 2. RSA level during a neutral stimulus, RSA reactivity to emotional video stimuli (distress, joy, and trauma videos) and RSA reactivity to memory stimuli (remote happy memory, trauma memory, mother's recall of the trauma memory) were also collected at both time points. Time 1 RSA level during a neutral stimulus was a significant predictor of Time 2 PTSD symptoms (controlling for age, Time 1 PTSD symptoms, Time 2 neutral RSA level), such that lower RSA during a neutral condition was related to higher PTSD symptoms. Also, Time 1 RSA reactivity in response to memory (but not video) stimuli, in the form of relatively less vagal withdrawal, was a significant predictor of more Time 2 PTSD symptoms (controlling for age, Time 1 PTSD symptoms, Time 2 RSA reactivity). This unique prospective study provides evidence for level of RSA and RSA reactivity as pre-existing clinical markers of stress sensitivity that predict psychopathology following a trauma.