title: Deep white matter hyperintensities in patients with bipolar depression, unipolar depression and age-matched control subjects.
abstract: OBJECTIVE
  Hyperintensities in the white matter of the brain (DWH) and in the periventricular area (PVH) seen on magnetic resonance imaging (MRI) have been reported to be more frequent in patients with bipolar disorder (BP) than in normal subjects. To examine this further we compared MRI of patients with BP with age-matched patients with major depressive disorder (unipolar depression, UP) and healthy control subjects.
  
  
  METHODS
  T2 weighted axial and coronal brain MRI scans were obtained from 13 patients in the depressive phase of BP, 11 with current UP and 19 age-matched control subjects. The degree of DWH and PVH present in each scan was determined using a standardized scoring method.
  
  
  RESULTS
  The PVH ratings were similar in the three groups of subjects. However, proportionately more BP patients had higher DWH scores than either UP patients or controls. Although this difference did attain statistical significant, a main effect of age was noted. Further, subjects over the age of 50 were under-represented in the UP group.
  
  
  CONCLUSIONS
  Notwithstanding the small total sample size and relative lack of older subjects in the UP group, the fact that almost twice as many BP patients showed more severe DWH suggests that patients with BP may be more vulnerable to develop these changes than UP patients and healthy controls.
authors.affiliation: Department of Psychological Medicine, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand.
authors.forename: Trevor
authors.initials: T
authors.lastname: Silverstone
authors.forename: Heather
authors.initials: H
authors.lastname: McPherson
authors.forename: Qunhuan
authors.initials: Q
authors.lastname: Li
authors.forename: Terry
authors.initials: T
authors.lastname: Doyle
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000704:Analysis of Variance; D001714:Bipolar Disorder / Q000175:diagnosis*; D001921:Brain / Q000473:pathology*; D003866:Depressive Disorder / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged