Insomnia characteristics and clinical correlates in Operation Enduring Freedom/Operation Iraqi Freedom veterans with post-traumatic stress disorder and mild traumatic brain injury: an exploratory study

Background There is limited data on chronic insomnia in Operation Enduring Freedom/Operation Iraqi Freedom (OEF/OIF) veterans, in whom post-traumatic stress disorder (PTSD) and mild traumatic brain injury (mTBI) often co-exist. Our aim was to compare sleep characteristics of three groups of OEF/OIF veterans: (1) healthy sleepers (HS), (2) those with insomnia associated with PTSD and mTBI (PTSD–mTBI), and (3) those with insomnia associated with PTSD alone. Methods Consecutive veterans with insomnia complaints (>6 months) were recruited over 6 months from the Miami VA Post Deployment clinic. Participants completed a sleep disorders clinical interview, medical history, and questionnaires about insomnia, sleepiness, pain, fatigue, depression, PTSD, and health-related quality of life. They underwent polysomnography (PSG) with 2 weeks of actigraphy (ACT) and sleep diaries. Results There were no differences in demographics or most questionnaire responses between PTSD and PTSD–mTBI groups. Subjective daytime sleepiness was significantly greater in PTSD–mTBI subjects compared with HS and PTSD participants. Significant co-morbid sleep disorders were noted in insomnia patients. PSG and ACT wake after sleep onset was significantly shorter in PTSD–mTBI subjects as compared with PTSD participants. Conclusion Insomnia patients with PTSD–mTBI were subjectively sleepier despite spending less time awake during the night than PTSD subjects, possibly as a consequence of head trauma.