[Interdisciplinary research strategies in geriatric psychiatry--studies and results in dementia and depressed patients].

Eighty-one patients (mean age: 66 +/- 9 years) who had been in gerontopsychiatric in-patient care were included in the study. As well as physical, psychiatric and neurological examinations, EEG, brain CT scanning and the determination of the Ischemic Scale were performed, in order to confirm the clinical diagnosis of dementia of Alzheimer type (DAT), dementia of vascular type (DVT) or multi-infarct dementia (MID), and depression in old age, as based on the DSM III criteria. A comprehensive psychological test battery was administered, to one section of the subjects. Our results indicate that EEG and Ischemic Score can differentiate patients with DAT and DVT to a satisfactory degree, whereas CT findings and psychometric assessment were apt to confirm the overall diagnosis of dementia (DAT/DVT) and depression. Patients with dementia showed memory impairment to a greater extent than depressive patients, as could be proved by a memory test (Syndrom-Kurztest). However, a dementia screening test (Information-Memory-Concentration Test) could more accurately differentiate dementia and depression. The application of a comprehensive psychometric testing procedure did not prove to be an effective diagnostic tool in the assessment of various stages of dementia. Short dementia tests and rating scales seem to be appropriate to distinguish depression from dementia, especially in cases of mild to moderate dementia. In patients with very mild and insignificant organic brain disturbances these screening methods fall short of diagnostic validity. Beyond this, there is a current need for assessment instruments in the evaluation of alterations in personality and affectivity, such as are seen in depression.