Incidence and relationship between behavioural and psychological symptoms in Alzheimer's disease

Objectives. To evaluate the frequency and type of psychological and behavioural symptoms in Alzheimer's disease (AD) patients in Poland, in various stages of the disease. Method One hundred and sixty-nine patients with a diagnosis of probable AD in Global Deterioration (GDS) stages 3, 4, 5, 6 and 7 of dementia were examined in a search for behavioural and psychological symptoms. Results. Behavioural and psychotic symptoms were most often found in GDS stages 5 and 6 of AD, except for depressive disorder, which was observed most frequently in GDS stage 4 and whose frequency decreased towards the terminal stages of dementia. From an analysis of the relationship between behavioural symptoms in the Polish AD patients, the following syndromes may be discriminated: psychotic syndrome (delusions and hallucinations), delusions with aggressive behaviour and hallucinations and anxiety. With more severe dementia, the syndromes, which could be the result of delirium, became more common. Conclusions. Diagnosis of delirium should be considered in moderately severe and severe dementia whenever a sudden change in patients' behaviour occurs. (C) 1998 John Wiley & Sons, Ltd.