title: State-dependent microstructural white matter changes in bipolar I depression.
abstract: Abnormalities in fronto-limbic-striatal white matter (WM) have been reported in bipolar disorder (BD), but results have been inconsistent across studies. Furthermore, there have been no detailed investigations as to whether acute mood states contribute to microstructural changes in WM tracts. In order to compare fiber density and structural integrity within WM tracts between BD depression and remission, whole-brain fractional anisotropy (FA) and mean diffusivity (MD) were assessed in 37 bipolar I disorder (BD-I) patients (16 depressed and 21 remitted), and 26 healthy individuals with diffusion tensor imaging. Significantly decreased FA and increased MD in bilateral prefronto-limbic-striatal white matter and right inferior fronto-occipital, superior and inferior longitudinal fasciculi were shown in all BD-I patients versus controls, as well as in depressed BD-I patients compared to both controls and remitted BD-I patients. Depressed BD-I patients also exhibited increased FA in the ventromedial prefrontal cortex. Remitted BD-I patients did not differ from controls in FA or MD. These findings suggest that BD-I depression may be associated with acute microstructural WM changes.
authors.affiliation: Laboratory of Psychiatric Neuroimaging (LIM-21), Department and Institute of Psychiatry, University of São Paulo Medical School, Centro de Medicina Nuclear, São Paulo, SP 05403-010, Brazil. marcus_zanetti@yahoo.com.br
authors.forename: Marcus V
authors.initials: MV
authors.lastname: Zanetti
authors.forename: Marcel P
authors.initials: MP
authors.lastname: Jackowski
authors.forename: Amelia
authors.initials: A
authors.lastname: Versace
authors.forename: Jorge R C
authors.initials: JR
authors.lastname: Almeida
authors.forename: Stefanie
authors.initials: S
authors.lastname: Hassel
authors.forename: Fábio L S
authors.initials: FL
authors.lastname: Duran
authors.forename: Geraldo F
authors.initials: GF
authors.lastname: Busatto
authors.forename: David J
authors.initials: DJ
authors.lastname: Kupfer
authors.forename: Mary L
authors.initials: ML
authors.lastname: Phillips
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D016880:Anisotropy; D001714:Bipolar Disorder / Q000473:pathology* / Q000503:physiopathology; D001921:Brain / Q000473:pathology*; D001931:Brain Mapping; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D018450:Disease Progression; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008297:Male; D008875:Middle Aged; D009413:Nerve Fibers, Myelinated / Q000473:pathology*; D009434:Neural Pathways / Q000473:pathology; D011569:Psychiatric Status Rating Scales; D013223:Statistics as Topic; D018709:Statistics, Nonparametric; D055815:Young Adult