title: Relationship between suicidality and impulsivity in bipolar I disorder: a diffusion tensor imaging study.
abstract: BACKGROUND
  Impulsivity is characteristic of individuals with bipolar disorder and may be a contributing factor to the high rate of suicide in patients with this disorder. Although white matter abnormalities have been implicated in the pathophysiology of bipolar disorder, their relationship to impulsivity and suicidality in this disorder has not been well-investigated.
  
  
  METHODS
  Diffusion tensor imaging scans were acquired in 14 bipolar disorder patients with a prior suicide attempt, 15 bipolar disorder patients with no prior suicide attempt, and 15 healthy volunteers. Bipolar disorder patients received clinical assessments including measures of impulsivity, depression, mania, and anxiety. Images were processed using the Tract-Based Spatial Statistics method in the FSL software package.
  
  
  RESULTS
  Bipolar disorder patients with a prior suicide attempt had lower fractional anisotropy (FA) within the left orbital frontal white matter (p < 0.05, corrected) and higher overall impulsivity compared to patients without a previous suicide attempt. Among patients with a prior suicide attempt, FA in the orbital frontal white matter region correlated inversely with motor impulsivity.
  
  
  CONCLUSIONS
  Abnormal orbital frontal white matter may play a role in impulsive and suicidal behavior among patients with bipolar disorder.
authors.affiliation: Center for Psychiatric Neuroscience, Feinstein Institute for Medical Research, Manhasset, NY, USA.
authors.forename: Katie
authors.initials: K
authors.lastname: Mahon
authors.forename: Katherine E
authors.initials: KE
authors.lastname: Burdick
authors.forename: Jinghui
authors.initials: J
authors.lastname: Wu
authors.forename: Babak A
authors.initials: BA
authors.lastname: Ardekani
authors.forename: Philip R
authors.initials: PR
authors.lastname: Szeszko
mesh_terms: D000328:Adult; D001714:Bipolar Disorder / Q000473:pathology*; D016022:Case-Control Studies; D056324:Diffusion Tensor Imaging; D005260:Female; D005625:Frontal Lobe / Q000473:pathology*; D006801:Humans; D007175:Impulsive Behavior / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009413:Nerve Fibers, Myelinated / Q000473:pathology*; D013406:Suicide, Attempted