Objective: To assess the correlates of daytime sleepiness in patients with a lifetime diagnosis of posttraumatic stress disorder (PTSD) and ongoing sleep disturbance not due to sleep apnea or other diagnosed sleep disorders.
Method: The sample consisted of 26 veterans receiving mental health care at the Minneapolis VA Medical Center, Minneapolis, Minnesota. The Epworth Sleepiness Scale was the primary outcome measure. Other sleep-related instruments consisted of the Pittsburgh Sleep Quality Scale, a daily sleep log, and daily sleep actigraphy. In addition, data included 3 symptom ratings (Posttraumatic Stress Disorder Checklist, Clinician Administered PTSD Scale [CAPS], and Beck Depression Inventory). Data were collected from 2003 to 2005. Current and lifetime PTSD diagnoses were based on DSM-IV criteria and were obtained by experienced psychiatrists using the CAPS interview.
Results: Univariate analyses showed that daytime sleepiness on the Epworth Sleepiness Scale was associated with daytime dysfunction on the Pittsburgh Sleep Quality Index (P < .001), less use of sleeping medication (P = .02), and more self-rated posttraumatic symptoms (P = .05). Within posttraumatic symptom categories, hypervigilance symptoms were more correlated with daytime sleepiness (P = .03) than were reexperiencing and avoidance symptoms (P = .09 for both).
Conclusion: In this selected sample, daytime sleepiness was most strongly and independently associated with daytime dysfunction.