Repeated intranasal oxytocin administration as early preventive intervention for PTSD : A randomized controlled trial.

As posttraumatic stress disorder (PTSD) develops in approximately 10% of trauma-exposed individuals, there is an urgent need for effective preventive interventions for PTSD [1]. Oxytocin administration was previously found to beneficially influence neurobiological and socio-emotional factors associated with increased PTSD risk [e.g. 2, 3]. Therefore, we hypothesized that intranasal oxytocin administration early post-trauma in trauma-exposed individuals could prevent PTSD development .
We performed a multi-center randomized double-blind placebo-controlled trial in 120 trauma-exposed emergency department patients, in which we investigated effects of repeated intranasal oxytocin administration (8 days/40 IU oxytocin/twice daily, initiated within 12 days posttrauma) on clinician-rated PTSD symptoms at 1.5, 3 and 6 months post-trauma. PTSD symptoms were assessed with the Clinician- Administered PTSD Scale (CAPS). We additionally assessed whether pre-treatment demographic and clinical characteristics moderated treatment effects, as previous studies showed that oxytocin administration effects might depend on interindividual factors (e.g. sex, presence and/or severity of psychiatric symptoms).
Intention-to-treat analyses showed no significant differences in clinician-rated PTSD symptoms at follow-up between oxytocin- (n = 53) and placebo-treated (n = 54) participants. However, baseline PTSD symptom severity significantly moderated the treatment effect on follow-up PTSD symptoms (p = 0.02): oxytocin treatment resulted in lower PTSD symptoms up to 6 months post-trauma compared to placebo treatment, only within participants with high baseline PTSD symptoms. Thus, our study provides initial support that repeated oxytocin administration early post-trauma shows promise for PTSD prevention in individuals. with high levels of distress early post-trauma. This is important as these individuals are at increased risk for subsequent PTSD.