title: Nightmares and Suicide in Posttraumatic Stress Disorder: The Mediating Role of Defeat, Entrapment, and Hopelessness.
abstract: OBJECTIVE
  Although nightmares appear to be related to suicidal behaviors, the mechanisms which underpin this relationship are unknown. We sought to address this gap by examining a multiple mediation hypothesis whereby nightmares were predicted to have an indirect effect on suicidal behaviors through perceptions of defeat, entrapment, and hopelessness.
  
  
  METHODS
  Data were collected from 91 participants who had experienced trauma and symptoms of posttraumatic stress disorder (PTSD). Nightmares were measured by summing the frequency and intensity ratings of relevant items on the Clinician-Administered PTSD Scale. Participants also completed questionnaire measures of suicidal behavior, hopelessness, defeat, and entrapment. Given the interrelations between insomnia, PTSD, and suicide, a measure of insomnia was included as a covariate. Furthermore, analyses were conducted with and without those participants who had comorbid depression.
  
  
  RESULTS
  Suicidal behaviors were higher in those participants who experienced nightmares (62%), in comparison to those who did not (20%). Bootstrapped analyses provided support for the hypothesized multistep mediational model. Specifically, nightmares were both directly and indirectly associated with suicidal behaviors, through perceptions of defeat, entrapment, and hopelessness, independent of comorbid insomnia and depression.
  
  
  CONCLUSIONS
  For the first time we show that the relationship between nightmares and suicidal behaviors is partially mediated by a multistep pathway via defeat, entrapment, and hopelessness. Clinically, our work highlights the importance of monitoring and targeting nightmares and perceptions of defeat, entrapment, and hopelessness when working with clients who have experienced trauma.
  
  
  CONCLUSIONS
  A commentary on this article appears in this issue on page 289.
authors.affiliation: School of Psychological Sciences, University of Manchester, UK.
authors.forename: Donna L
authors.initials: DL
authors.lastname: Littlewood
authors.affiliation: School of Psychological Sciences, University of Manchester, UK.
authors.forename: Patricia A
authors.initials: PA
authors.lastname: Gooding
authors.affiliation: Institute of Population Health, University of Manchester, UK.
authors.forename: Maria
authors.initials: M
authors.lastname: Panagioti
authors.affiliation: Sleep and Circadian Neuroscience Institute, University of Oxford, UK.
authors.forename: Simon D
authors.initials: SD
authors.lastname: Kyle
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D004325:Dreams; D004644:Emotions; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013313:Stress Disorders, Post-Traumatic / Q000523:psychology*; D059020:Suicidal Ideation; D013405:Suicide / Q000523:psychology*; D011795:Surveys and Questionnaires; D055815:Young Adult
keywords: defeat; depression; entrapment; hopelessness; insomnia; nightmares; posttraumatic stress disorder; suicidal ideation