title: Sleep disorders and the interpersonal-psychological theory of suicide: independent pathways to suicidality?
abstract: BACKGROUND
  Although sleep disorders are a risk factor for suicidal behavior little research has examined why sleep disorders confer suicide risk. The present study examined the relation between two sleep disorders, insomnia symptoms and nightmares, and suicide risk in the context of Joiner's interpersonal-psychological theory of suicide (IPTS).
  
  
  METHODS
  The present study utilized two large samples (N=747 and 604) recruited from two large public universities in the Southeast. Both studies included measures of insomnia symptoms, nightmares, depressive symptoms, and prior suicide attempts. In addition, study one contained a measure of suicide risk.
  
  
  RESULTS
  In study 1, the relations between insomnia symptoms and both suicide risk and prior attempts were not significant after controlling for the IPTS. However, nightmares were related to both suicide risk and suicide attempts independent of the IPTS. Furthermore, nightmares nearly missed significance in the prediction of suicide risk (p=0.054) and significantly predicted suicide attempts even after controlling for depressive symptoms. In study 2, both insomnia and nightmares were found to be significantly associated with prior suicide attempts after controlling for the IPTS and depressive symptoms.
  
  
  CONCLUSIONS
  The study is limited by its use of a college sample and cross-sectional design.
  
  
  CONCLUSIONS
  These studies suggest that the IPTS may not explain the relation between sleep problems and suicidality. More research is needed to understand the mechanism by which sleep disorders confer suicide risk, which is clinically relevant as it may inform specific interventions to reduce the adverse effects of sleep disorders.
authors.affiliation: Department of Psychology, Mississippi State University, P.O. Box 6161, Mississippi State, MS 39762, United States; Menninger Department of Psychiatry, Baylor College of Medicine, Houston, TX, United States. Electronic address: mnadorff@psychology.msstate.edu.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Nadorff
authors.forename: Michael D
authors.initials: MD
authors.lastname: Anestis
authors.forename: Sarra
authors.initials: S
authors.lastname: Nazem
authors.forename: H
authors.initials: H
authors.lastname: Claire Harris
authors.forename: E
authors.initials: E
authors.lastname: Samuel Winer
mesh_terms: D000293:Adolescent; D000328:Adult; D003625:Data Collection; D004325:Dreams / Q000523:psychology*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D011581:Psychological Tests; D011582:Psychological Theory; D012307:Risk Factors; D007319:Sleep Initiation and Maintenance Disorders / Q000523:psychology*; D013405:Suicide / Q000523:psychology*; D013406:Suicide, Attempted / Q000523:psychology / Q000706:statistics & numerical data; D011795:Surveys and Questionnaires; D055815:Young Adult
keywords: Depression; Insomnia symptoms; Interpersonal–psychological theory of suicide; Nightmares; Suicide risk