Abstract
Background: A complex bidirectional relationship exists between sleep and post-traumatic stress disorder (PTSD). Previous research reporting a strong association between sleep and PTSD has largely examined older military veteran populations, with military-related confounders potentially magnifying this effect. Less is known whether this association remains strong in younger civilian adults.Objective: This study examined the relationship between sleep disturbances, PTSD symptoms and PTSD symptom clusters in a young adult population with mixed trauma histories, while investigating the role of sex, chronotype and trauma chronicity in moderating this relationship.Method: In this cross-sectional study, 337 trauma-exposed undergraduate students (269 females, 68 males) aged 17-66 (M = 20.24, SD = 5.20) completed a battery of online questionnaires measuring trauma history, PTSD symptom severity, sleep disturbances, chronotype, mood state and alcohol use.Results: Trauma-exposed participants with and without probable PTSD demonstrated a significant positive relationship between sleep disturbances and PTSD symptom severity, F(3, 333) = 58.24, p < .001, R(2) = .34, although this relationship was not significantly moderated by any of the hypothesised factors. Additionally, sleep quality was significantly and positively associated with all four PTSD symptom clusters (re-experiencing, hyperarousal, avoidance, and negative mood).Conclusions: The sleep-PTSD relationship in a mixed-trauma, young adult population is consistent with what has been found in military veteran populations. The strong association between sleep and PTSD highlight the potential for targeted sleep interventions to also benefit young adults with PTSD and may reduce PTSD risk in those who have recently experienced a traumatic event.