0339 Risk factors and Correlates of Insomnia across U.S. Army Deployment Cycle

Introduction The behavioral model of insomnia theorizes predispositions make people susceptible to developing insomnia in the face of precipitants. Few comprehensive longitudinal studies have investigated both predispositions and precipitants in the prediction of the development of insomnia. Many military service members face a significant potential precipitant, deployment. The current study is a prospective examination to identify predispositions and precipitants of insomnia from pre- to post-deployment in military service members. Methods Participants were part of a parent study that assessed US Army personnel (N = 4,104) pre-deployment and again in a smaller subsample (n = 1,828) willing to complete post-deployment assessments, using self-report measures of insomnia (i.e., Insomnia Severity Index; ISI) as well demographics, resilience and personality, social support, deployment stress, adversity and trauma, and other mental and physical health symptoms. Results In the subsample (n=1,828), 18% had clinically significant insomnia (ISI < 15) at baseline and the rate of insomnia increased to 31% at post-deployment. Pre- to post-deployment change in insomnia symptoms showed that 63% of the sample had no insomnia at both time points, 7% actually had insomnia that remitted (i.e., insomnia at pre-deployment but not post-deployment), 19% had new onset insomnia, and 11% had chronic insomnia (i.e., both time points). Preliminary logistic regression analyses of no insomnia vs. onset insomnia showed fewer deployments and greater insomnia symptoms (despite ISI < 15), history of stressful life events, number of children, PTSD symptoms, history of head injury, anxiety and being enlisted at baseline, all predicted onset insomnia at post-deployment. Future analyses will examine predictors of remitted vs. chronic insomnia and examine differences between all groups on deployment related stressors and post-deployment mental and physical health factors. Conclusion These are the first data to our knowledge to attempt to identify true predispositions and precipitants for the development of insomnia in either a civilian or a military sample. Implications will be discussed in depth at the conference. Support (If Any) W81XWH-08-2-0110 (Dr. Williamson),W81XWH-08-02-109 (Dr. Peterson), and W81XWH-10-1-0828 (Dr. Taylor) and 1I01CU000144-01 (Dr. Peterson, Dr. Williamson, and Dr. Taylor).