THE DIFFERENTIATION BETWEEN DEPRESSION AND DEMENTIA IN THE VERY OLD

Key questions in the psychiatric understanding of elderly people are the development of psychiatric morbidity, its phenomenology in old age, the differentiation between 'normal' and 'pathological' ageing, the interrelatedness of different types of mental disorders, their relation to somatic morbidity, and their consequences in daily life. Under the hypothesis of the de-differentiation of psychopathological features in old age, the relation between depression and dementia is studied. Contrary to most gerontopsychiatric research, the Berlin Aging Study (BASE) permits an analysis of these questions in a heterogeneous and primarily non-clinical community population. Initial data from the first 360 intake assessments and the first 156 intensively studied participants of BASE are presented. Results show that, even in very old individuals, depression and dementia still exhibit clearly distinctive psychopathological features. Prevalence rates in consecutive age groups show an age-related increase for dementia but not for depression. Nevertheless dementia and depression do not seem to be fully independent, because our data indicate a masking or extinction of depressive symptoms by dementia. Finally, both disorders have a similarly significant negative impact on independence, comparable to that of somatic morbidity.