Poor sleep quality and changes in objectively recorded sleep after traumatic brain injury: a preliminary study.

Objectives: To evaluate changes in sleep quality and objectively assessed sleep parameters after traumatic brain injury (TBI) and to investigate the relationship between such changes and mood state and injury characteristics.
Design: Survey and laboratory-based nocturnal polysomnography.
Setting: Sleep laboratory.
Participants: Ten community-based subjects with moderate to very severe TBI and 10 age- and sex-matched controls from the general community.
Interventions: Not applicable.
Main Outcome Measures: Pittsburgh Sleep Quality Index for self-report sleep quality, nocturnal polysomnography for objective sleep recording, and Hospital Anxiety and Depression Scales.
Results: Compared with controls, TBI patients reported significantly poorer sleep quality and higher levels of anxiety and depression. Objective sleep recording showed that TBI patients showed an increase in deep (slow wave) sleep, a reduction in rapid eye movement sleep, and more frequent nighttime awakenings. No significant relationship was observed between these changes in sleep and injury severity or time since injury. Anxiety and depression covaried with the observed changes in sleep.
Conclusions: The findings contribute to the growing body of evidence that sleep is involved in the physiologic processes underlying neural recovery. The association between anxiety and depression and the observed changes in sleep in TBI patients warrants further examination to determine whether a causative relationship exists.