[Psychobehavioral disorders in severe dementia].

Behavioral and psychological symptoms of dementia (BPSD) are not included in the diagnostic criteria for dementia or in the assessment tools for grading its severity. However, they constitute a major part of the caregivers' burden and the main cause for institutionalization. They are, for one part, the direct consequence of the brain lesions, but, for another part, they result from the psychological reactions of the patients to their cognitive deficits or their relational difficulties with their family or carers. Despite speech disorder and mind disruption, patients with severe dementia still have a psychic and relational life, which is expressed through BPSD. Many BPSD are of short duration and can be improved by a better understanding, psychological and behavioral approach. However, psychotropic drugs are often useful or necessary, but, due to the frailty of the patients with severe dementia, their use should be very cautious.