title: Risk factors for suicide in bipolar I disorder in two prospectively studied cohorts.
abstract: BACKGROUND
  These analyses were undertaken to determine whether similar risk factors for suicide emerged across two prospectively studied cohorts of individuals with bipolar I disorder.
  
  
  METHODS
  The NIMH Collaborative Study of Depression (CDS) recruited 288 patients with bipolar I disorder from 1978-1981 as they sought treatment. Subjects were followed semiannually and then annually for up to 30 years. The Bipolar Genomics studies identified individuals through clinical referrals and advertisement. Clinical follow-up did not occur but personal identifiers of 1748 were matched with National Death Index (NDI) records. Kaplan-Meier survival analyses tested ten potential risk factors.
  
  
  RESULTS
  The CDS and Genomic follow-ups encompassed 12,667 and 4529 person-years, respectively. Suicides/100 person-years were 0.26 and 0.055. The demographic or clinical variables that predicted suicide differed considerably in the two cohorts. The odds ratio for suicide for those with any history of suicide attempt was 2.3 and 2.8, respectively, and was the third highest odds ratio of the tested risk factors in both studies.
  
  
  CONCLUSIONS
  
  
  
  CONCLUSIONS
  Differences in the sources of participants in studies of suicide risk may result in marked differences across studies in both rates of suicide and in risk factors. A history of suicide attempt is a relatively robust risk factor across samples.
authors.affiliation: University of Iowa Carver College of Medicine, Department of Psychiatry, United States. Electronic address: william-coryell@uiowa.edu.
authors.forename: William
authors.initials: W
authors.lastname: Coryell
authors.affiliation: University of Iowa Carver College of Medicine, Department of Psychiatry, United States.
authors.forename: Abby
authors.initials: A
authors.lastname: Kriener
authors.affiliation: University of Iowa Carver College of Medicine, Department of Psychiatry, United States.
authors.forename: Brandon
authors.initials: B
authors.lastname: Butcher
authors.affiliation: Indiana University, Department of Psychiatry, United States.
authors.forename: John
authors.initials: J
authors.lastname: Nurnberger
authors.affiliation: Johns Hopkins University, Department of Psychiatry, United States.
authors.forename: Francis
authors.initials: F
authors.lastname: McMahon
authors.affiliation: University of Pennsylvania, Department of Psychiatry, United States.
authors.forename: Wade
authors.initials: W
authors.lastname: Berrettini
authors.affiliation: University of Iowa Carver College of Medicine, Department of Psychiatry, United States.
authors.forename: Jess
authors.initials: J
authors.lastname: Fiedorowicz
mesh_terms: D000328:Adult; D001714:Bipolar Disorder / Q000401:mortality*; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D011446:Prospective Studies; D012307:Risk Factors; D013405:Suicide / Q000706:statistics & numerical data*; D013406:Suicide, Attempted / Q000706:statistics & numerical data; D055815:Young Adult
keywords: Bipolar disorder; Risk factors; Suicide; Suicide attempts