title: Factors associated with a depressive disorder in Alzheimer's disease are different from those found for other dementia disorders.
abstract: BACKGROUND
  This study explores factors associated with depression in Alzheimer's disease (AD) compared with mild cognitive impairment (MCI) and other dementia disorders.
  
  
  METHODS
  In a prospective study we included 195 patients: 31 with MCI, 112 with AD and 52 with other dementias.
  
  
  RESULTS
  According to the ICD-10 and the DSM-IV criteria, 88 (44.1%) and 59 (30.3%), respectively, had a depressive disorder. An adjusted multiple regression analysis showed that previous depression (p < 0.05) was significantly associated with depression in AD patients. Severity of dementia (p < 0.05) was significantly associated with a depressive disorder in a group of patients with frontotemporal dementia, vascular dementia, or dementia due to Lewy Body disease or Parkinson's disease.
  
  
  CONCLUSIONS
  We found different factors associated with a depressive disorder in AD compared to those found for other dementia disorders.
authors.affiliation: Norwegian Centre for Dementia Research, Centre for Ageing and Health, Department of Geriatric Medicine, Oslo University Hospital, Ullevål, Norway.
authors.forename: Maria Lage
authors.initials: ML
authors.lastname: Barca
authors.forename: Knut
authors.initials: K
authors.lastname: Engedal
authors.forename: Jerson
authors.initials: J
authors.lastname: Laks
authors.forename: Geir
authors.initials: G
authors.lastname: Selbaek