Prominence of Hyperarousal Symptoms Explains Variability of Sleep Disruption in Posttraumatic Stress Disorder

Objective: Disrupted sleep is a central feature of posttraumatic stress disorder (PTSD). The precise nature of that disruption is not agreed upon, however, and there is no explanation for why sleep disruptions are detected in some PTSD-diagnosed individuals but not in others. We tested the novel proposition that PTSD-diagnosed individuals with prominent hyperarousal symptoms will have more disrupted sleep than those without such symptoms. Method: We assigned each of 57 female volunteers to 1 of 4 groups: PTSD + Hyperarousal (PTSD + HYP; n = 14), PTSD - Hyperarousal (n = 13), depression (n = 14), or healthy control (n = 16). Each experienced 1 night of polysomnographic recording in a sleep laboratory. Results: General linear modeling confirmed that group status (i.e., being in the PTSD + HYP group rather than the other groups) predicted disrupted sleep quality most strongly. PTSD patients with prominent hyperarousal symptoms, relative to those without such symptoms, experienced reduced sleep efficiency, spent more time awake after sleep onset, and self-reported poorer sleep quality. Conclusion: These preliminary findings, although requiring replication in larger samples, suggest an important association between hyperarousal symptoms and sleep quality in PTSD, and may help explain why some PTSD-diagnosed individuals experience markedly disrupted sleep whereas others do not.