Natural history of behavioural changes and psychiatric symptoms in Alzheimer's disease - A longitudinal study

Background Alzheimer's disease and other types of dementia are characterise d by numerous psychiatric and behavioural changes. Little is known of their natural history. Aims To investigate the sequence and pattern of these changes throughout th e course of dementia. Method One hundred people, initially living at home w ith carers, entered a prospective, longitudinal study. At four-monthly inte rvals, behavioural and psychiatric symptoms were assessed using the Present Behavioural Examination and Mini-Mental State Examination. Follow-up conti nued for up to nine years (mean 3.3 years; s, d. 2.4). Patterns of onset an d disappearance of these symptoms, their sequence and association with time of death and cognitive decline were analysed. Autopsy confirmed a diagnosi s of pure Alzheimer's disease in 48 subjects. Data for this subgroup are pr esented. Results Some changes tend to occur earlier than others but changes can occu r at almost any time in the course of dementia. Conclusions The natural history of behaviour changes in Alzheimer's disease shows great individual variation although some changes tend to follow a re cognisable sequence. Declaration of interest Project funded by the Medical Research Council. Fur ther funding from Eli Lilly; C. G: F. supported by the Wellcome Trust.