Longitudinal course of behavioural and psychological symptoms of dementia: systematic review

BACKGROUND: More information about the pattern of behavioural and psychological symptoms of dementia (BPSD) in the course of dementia is needed to inform patients and clinicians and to design future interventions.

AIMS: To determine the persistence and incidence of BPSD and their relation to cognitive function, in individuals with dementia or in cohorts investigated for dementia onset.

METHOD: A systematic literature review analysed the baseline prevalence, persistence and incidence of 11 symptoms. The review was conducted according to established guidelines with the exception that we could not exclude the possibilities of bias in the studies examined.

RESULTS: The 59 included studies showed considerable heterogeneity in their objectives and methods. The symptoms hyperactivity and apathy showed high persistence and incidence; depression and anxiety low or moderate persistence and moderate incidence; and psychotic symptoms low persistence with moderate or low incidence.

CONCLUSIONS: Despite heterogeneity across studies in terms of setting, focus and length of follow-up, there were clinically relevant differences in the longitudinal courses of different BPSD. Apathy was the only symptom with high baseline prevalence, persistence and incidence during the course of dementia.