Prevalence and mental health correlates of sleep disruption among military members serving in a combat zone.

Sleep disruption is an emergent military health issue, but remarkably little is known of its prevalence or comorbidities in the combat zone. This study was designed to quantify the prevalence and mental health correlates of sleep disruption among military personnel serving within a ground combat zone during Operation Enduring Freedom. This was a large, cross-sectional survey of active duty and reserve U.S. Navy personnel (N = 3,175). Self-reported sleep measures included total hours of sleep per day, total hours of sleep required to feel well-rested, difficulty falling asleep, and difficulty staying asleep. The survey also measured mental health symptoms, including post-traumatic stress symptoms, anxiety, and depression. Participants reported an average of 5.9 hours of sleep per day despite requiring on average 6.8 hours to feel well rested. More than half (56%) were classified as sleep deficient, and 67% reported 6 or fewer hours of sleep per day. Adjusted for covariates, individuals endorsing sleep disruption were at substantially elevated risk of meeting criteria for post-traumatic stress disorder, generalized anxiety disorder, and major depressive disorder. This study documents the prevalence of sleep disruption in a very large and difficult-to-access sample of military members serving in a combat zone, and details robust associations with mental health.