Geriatric depression and its relation with cognitive impairment and dementia

Different subtypes of depressive syndromes exist in late life; many of them have cognitive impairment and sometimes it is difficult to differentiate them from dementia. This research aimed to investigate subtypes of geriatric depression associated with cognitive impairment, searched for differential variables and tried to propose a study model. A hundred and eighteen depressive patients and forty normal subjects matched by age and educational level were evaluated with an extensive neuropsychological battery, scales to evaluate neuropsychiatric symptoms and daily life activities (DLA). Depressive patients were classified in groups by SCAN 2.1: Major Depression Disorder (MDD) (n: 31), Dysthymia Disorder (DD) (n: 31), Subsyndromal Depression Disorder (SSD) (n: 29), Depression due to Dementia (n: 27) (DdD). Neuropsychological significant differences (p < 0.05) were observed between depressive groups, demonstrating distinctive cognitive profiles. Moreover, significant differences (p < 0.05) were found in DLA between DdD vs all groups and MDD vs controls and vs SSD. Age of onset varied in the different subtypes of depression. Beck Depression Inventory (BDI) and Mini Mental State Examination (MMSE) were significant variables that helped to differentiate depressive groups. Significant correlations between BDI and Neuropsychological tests were found in MDD and DD groups. Depressive symptoms and its relation with neuropsychological variables, MMSE, cognitive profiles, DLA and age of onset of depression should be taken into consideration for the study of subtypes of geriatric depression.