Prevalence, correlates and course of behavioural and psychological symptoms of dementia in the population

BACKGROUND: Behavioural and psychological symptoms of dementia (BPSD) are major contributors to the burden of dementia. AIMS: To describe the prevalence, correlates and course of BPSD in the population of England and Wales. METHOD: The prevalence of 12 symptoms was estimated in 587 participants with dementia and 2050 participants without dementia as part of a population-based longitudinal study of ageing. The effect of risk factors and the factor structure were estimated using 1782 interviews provided by participants with dementia throughout the study. RESULTS: Each symptom apart from sleeping problems was more common in the population with dementia. The co-occurrence of the symptoms was explained by a four-factor solution, corresponding to psychosis/apathy, depression/anxiety, irritability/persecution and wandering/sleep problems. Psychosis occurred more frequently with declining cognition. Anxiety and depression were more common in younger individuals and in those with poor self-reported health. Persistence varied between symptoms. CONCLUSIONS: Behavioural and psychological symptoms of dementia affect nearly all people with dementia. Symptoms co-occur, and the symptoms that affected individuals experience are related to their socio-demographic and clinical characteristics.