Factors Associated with a Depressive Disorder in Alzheimer’s Disease Are Different from Those Found for Other Dementia Disorders

BACKGROUND: This study explores factors associated with depression in Alzheimer's disease (AD) compared with mild cognitive impairment (MCI) and other dementia disorders. METHOD: 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. CONCLUSION: We found different factors associated with a depressive disorder in AD compared to those found for other dementia disorders.