1067 Replicative and Non-Replicative Nightmares in the Development of Posttraumatic Stress Disorder

Abstract

Introduction: Nightmares are a frequent and disturbing symptom of posttraumatic stress disorder (PTSD). They are associated with sleep disruption and increased psychopathology. There is growing evidence that different types of nightmares may differ in their effects on psychopathology. Previous findings suggest that nightmares that are close replications of the experienced traumatic event might be especially important in the development of PTSD. This study investigated trauma-related (replicative) and non-traumarelated (non-replicative) nightmares as predictors of PTSD in a civilian sample. Method(s): Participants were recruited from the general public of the greater Boston area. The sample consisted of 108 participants who had experienced a psychological trauma in the past 2 years (e.g. sexual or physical assaults and accidents). The criteria for PTSD were met by 49% of participants. PTSD diagnosis was assessed using the Structured Clinical Interview for DSM-IV-TR Axis I Disorders-Non-Patient Edition. Participants received an Actiwatch 2 (Philips Respironics, Bend, OR) and a sleep diary for sleep measurements over an average of 14 consecutive nights. The diary included a prospective nightmare assessment and an item assessing the relatedness of each nightmare to traumatic events. Logistic regression analyses were performed with PTSD as the categorical outcome variable. Result(s): Our analyses showed that replicative nightmares were the only statistically significant predictor of PTSD (OR = 1.2, p = .027), while controlling for age, sex, time since the traumatic event, and actigraphy total sleep time and minutes awake after sleep onset. All of these variables, including non-replicative nightmares, did not significantly predict PTSD in our analyses. Conclusion(s): This study confirms and adds to the existing knowledge of nightmares and the importance of the degree to which they replicate the trauma in the development of PTSD. These findings underline the potential role of specific nightmare treatments after traumatic events, with a special focus on replicative nightmares.