title: Insomnia as predictor versus outcome of PTSD and depression among Iraq combat veterans.
abstract: OBJECTIVE
  The study conducted a longitudinal assessment of insomnia as an antecedent versus consequence of posttraumatic stress disorder (PTSD) and depression symptoms among combat veterans.
  
  
  METHODS
  Two postdeployment time points were used in combination with structural equation modeling to examine the relative strength of two possible directions of prediction: insomnia as a predictor of psychological symptoms, and psychological symptoms as a predictor of insomnia. Participants were active duty soldiers (N = 659) in a brigade combat team who were assessed 4 months after their return from a 12-month deployment to Iraq, and then again eight months later.
  
  
  RESULTS
  Although both insomnia and psychological symptoms were associated at both time periods and across time periods, insomnia at 4 months postdeployment was a significant predictor of change in depression and PTSD symptoms at 12 months postdeployment, whereas depression and PTSD symptoms at 4 months postdeployment were not significant predictors of change in insomnia at 12 months postdeployment.
  
  
  CONCLUSIONS
  Results support the role of insomnia in the development of additional psychological problems and highlight the clinical implications for combat veterans, to include the importance of longitudinal assessment and monitoring of sleep disturbances, and the need for early intervention.
authors: U.S. Army Medical Research Unit-Europe, Walter Reed Army Institute of Research, Heidelberg, Germany. kathleen.wright@us.army.mil
authors: Kathleen M
authors: KM
authors: Wright
authors: Thomas W
authors: TW
authors: Britt
authors: Paul D
authors: PD
authors: Bliese
authors: Amy B
authors: AB
authors: Adler
authors: Dante
authors: D
authors: Picchioni
authors: Dewayne
authors: D
authors: Moore
mesh_terms: D000328:Adult; D015984:Causality; D003130:Combat Disorders / Q000175:diagnosis / Q000453:epidemiology / Q000534:rehabilitation; D015897:Comorbidity; D003863:Depression / Q000175:diagnosis / Q000453:epidemiology* / Q000534:rehabilitation; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D054542:Iraq War, 2003-2011; D008137:Longitudinal Studies; D008297:Male; D008889:Military Personnel / Q000523:psychology; D008960:Models, Psychological; D011379:Prognosis; D007319:Sleep Initiation and Maintenance Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000534:rehabilitation; D013313:Stress Disorders, Post-Traumatic / Q000175:diagnosis / Q000453:epidemiology* / Q000534:rehabilitation; D014481:United States / Q000453:epidemiology; D014728:Veterans / Q000523:psychology*