Objective: To investigate in trauma survivors the predictive validity of heightened physiological responsivity to script-driven imagery for the development of posttraumatic stress disorder (PTSD) and to evaluate the interactive effect of survivors' sex. Physiological responses to idiosyncratic trauma reminders may be predictive of later PTSD. The majority of previous studies have been cross sectional and have produced mixed findings. Sex differences may contribute to this heterogeneity.
Methods: Heart rate (HR) and respiratory sinus arrhythmia were measured at 2 weeks post trauma in 158 assault survivors during baseline and as they listened to an idiosyncratic trauma script. At 6 months, 15.2% of male and 28.1% of female participants met the diagnostic criteria for PTSD.
Results: Generalized linear model and logistic regression analyses showed that HR response to script-driven imagery and sex interacted in predicting PTSD symptom severity at 6 months. Women had greater PTSD symptom severities overall. Female HR responders to script-driven imagery showed the highest PTSD symptom severities and were almost three times more likely to develop PTSD at 6 months compared with men and female nonresponders (odds ratio, 2.72; 95% confidence interval, 1.13-6.57). Respiratory sinus arrhythmia responder type did not predict PTSD (odds ratio, 0.64; 95% confidence interval, 0.30-1.33).
Conclusion: Female trauma survivors who respond to trauma reminders with increased HR may be at particular risk of developing PTSD. Physiological reactivity to trauma cues may be a useful index for screening and prevention of PTSD.